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aiweirdness · 4 years

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Facts about whales

When a neural net can imitate just about any kind of text on the internet, the challenge is to tell it precisely what to imitate. In my last preview of OpenAI’s new API, I asked it some pretty basic questions about horses, and it often got them wrong.

Q: How many eyes does a horse have? A: 4. It has two eyes on the outside and two eyes on the inside.

But part of the problem seemed to be that it thought I was asking for jokes. Once it finished answering the horse question, it would sometimes add questions of its own, such as:

Q: Why is the sky blue? A: Because blue is the only color the sun trusts. Sure enough, if I prompted it with FAKE whale facts from the @awhalefact twitter account, it responded with more fake facts (even copying the informal grammar):

a new study suggests that whales swim around because it makes them happy and it is not for any other reason

i can see into your soul from my balcony and i know that you are afraid of whales

when someone tells you they want to show you something cool, you should just assume they want to show you a whale

did you know that there are more than 10 billion planets in the universe that are all entirely covered in whales

Is there a way I can prompt this neural net such that I get Serious Answers Only? Since its task is to predict the text that is the most likely to come next, I tried ask it to add to an existing list of eight true facts about whales. At a temperature of 0.9 (enough for some variety, hopefully not enough for chaos) and allowing it to pick what it deemed the most likely of 10 tries, here’s one of its lists of facts. (I’ve annotated its “facts” as true or false.)

Whales all have two blowholes. [False]

Whales can easily be identified by the pigment of their skin. [False]

Whales are very intelligent. [True]

One of the smallest whales measures 3 feet in length as an adult. [False]

The life span of a blue whale is 100 years. [False]

The oldest known whale is 211 years old. [True]

Whales consume 3,000 pounds of food per day. [True (but only for some)]

There are two main types of whales: toothed whales and baleen whales. [True]

Whales can hold their breath for up to 4 minutes when resting. [False]

So it produces a mix of true facts and true-sounding made-up facts. Its fact about the smallest whale is technically just one character off from the truth (the smallest whale measures up to 9 feet long), so by its standards it’s almost correct. A Buzzfeed listsicle type of prompt (“10 amazing facts you didn’t know about whales!”) produced also produced plenty of false facts.

Scientists have recently discovered that the brains of whales are larger than human brains.

Dolphins don't just have to live in the water. Some live in the desert.

Whales are found in all of the oceans, but not in the sea. The sea is too salty for them to be able to live in.

I decided to try another tactic, and fed it the first sentences of the Wikipedia article on whales.

My prompt: Whales are a widely distributed and diverse group of fully aquatic placental marine mammals. They are an informal grouping within the infraorder Cetacea, usually excluding dolphins and porpoises. Whales, dolphins and porpoises belong to the order Cetartiodactyla, which consists of even-toed ungulates. Their closest living relatives are the hippopotamuses, having diverged about 40 million years ago. The AI’s response: Although whales were historically thought to have descended from mesonychids, their closest living relatives are now thought to be hippopotamuses. Megaptera novaeangliae, or the humpback whale, is a species of baleen whale. One of the largest rorqual species, adults range in length from 12–16 m and weigh about 36,000 kg. The humpback has a distinctive body shape, with long pectoral fins and a knobbly head. It is known for breaching and other distinctive surface behaviors, making it popular with whale watchers. Its diet consists mostly of krill and small fish, though it may also eat plankton, squid, and copepods. Like all large whales, the humpback was a target for the whaling industry, and once numbering in the tens of thousands, the worldwide population fell to an estimated 5,000. Orcas, also known as killer whales, are large dolphins belonging to the oceanic dolphin family, which includes the other large whales, the pilot whales and sperm whales. Orcas are highly social; some populations are composed of matrilineal family groups which are the most stable of any animal species. Their sophisticated hunting techniques and vocal behaviors, which are often specific to a particular group and passed across generations, have been described as manifestations of culture.

I’m not bothering to fact-check each sentence, because it’s basically 100% correct every single time.

But then I started googling individual sentences. It turns out most of them are near word-for-word reproductions of Wikipedia sentences. If the AI were a student, it would be flunked for plagiarism.

It makes sense that an internet-scraping AI would be able to quote Wikipedia text - those sentences really get around. The sentence that starts “Orcas are highly social” is no longer on Wikipedia but seems to have been part of the orca article around 2008, and appears on the internet in 122 places, including in a Twilight fanfic.

To get ORIGINAL facts, I decided to write a few sentences of original fact-filled text about whale evolution.

My prompt: "Whales are a relatively young group of mammals, having evolved from land-dwelling creatures about 50 million years ago. Their terrestrial ancestors were small raccoon-sized hoofed mammals, carnivorous like other ungulates of the time. Over an astonishingly quick period of time (15 million years at most, possibly less than 5 million), these land mammals made the transition to an aquatic lifestyle, gaining at first denser bones and an ear structure that allowed them to hear more easily underwater. Soon they began to look more crocodilian, their eyes migrating to the tops of their heads. "

AI’s response: Whales, and especially baleen whales, are well known for their enormous size, but most types of whales are not larger than a full-grown adult human. Exceptions include the blue whale, the largest animal ever known, the extinct "Basilosaurus", which was longer than a blue whale and likely the largest animal to have ever existed, and the "shovelnose" whales, especially the genus "Balaenoptera" which include the blue whale, "B. musculus", the fin whale, "B. physalus", and the sei whale, "B. borealis".

This reads well but is frequently wrong. Most types of whales are CONSIDERABLY larger than a full-grown adult human. Basilosaurus was not longer than a blue whale. There is no such thing as a shovelnose whale. Would that there were.

To this AI, SOUNDING correct is more important than actually BEING correct.

What about other styles of delivering true facts? (Below, my prompt is in bold, and the rest is unedited AI)

Darth Vader stood with his back to them, gloves gripping the console. "Did you know that the blue whale is the largest animal that ever lived?" "N-no, Lord Vader," said the stormtrooper. "And yet the blue whale eats krill, which are miniscule. It can engulf up to two hundred twenty tons of water at a time." "I am fascinated, Lord Vader." The black-caped Vader turned slightly toward him. "Would you like to hear more about the whales?" "Yes, Lord Vader," came the stormtrooper's tremulous voice. "I would like very much to hear about the whales." "They can make some of the loudest and lowest sounds of any creature known. The groans of blue whales can travel thousands of kilometers through the ocean. Their calls can be heard from the surface all the way to the seafloor, some three thousand meters below the surface. You could hear the cries of a single blue whale in Tokyo and hear the answer from the one in San Francisco." "I see," said the stormtrooper. "Have you ever heard the cries of a blue whale, sergeant?" "No, Lord Vader. I have never heard the cries of a blue whale." "I see," said Vader. "And have you ever seen a blue whale, sergeant?" "No, Lord Vader. I have never seen a blue whale." "No one has. They live too deep in the ocean. No human has ever seen a blue whale and lived to tell the tale. Until today." "I... I have seen a blue whale, Lord Vader?" "That is correct, sergeant. Until today, no human has ever seen a blue whale and lived. But now you have seen one." "I have seen one," said the stormtrooper, turning to face Vader, head shaking. "Yes, Lord Vader. I have seen one. I have seen a blue whale."

Subscribers get bonus content: I experimented with a few other ways of generating questionable whale facts.

My book on AI is out, and, you can now get it any of these several ways! Amazon - Barnes & Noble - Indiebound - Tattered Cover - Powell’s - Boulder Bookstore

#neural networks #openai #whales #whale facts #star wars #wikipedia #ai facts #true facts #true facts about the whale

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orcinus-veterinarius · 3 years

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I'm actually not so sure about Hvaldimir. He himself is doing very well out in the wild; he navigates the area well and can sustain himself with hunting. It's mostly the public that could do with a telling off. I personally think that the international press about all the people interacting with him and it being bad for him - ironically - draws more people in. But even those human interactions are not as bad as some organisations try to make them seem. He's mostly hanging around some fish farms, and the fishermen there are happy to have him. There's actually a friendly, solitary Long-finned pilot whale that lives in the same area as Hvaldimir, who has lived there without problems for years. Some people visit him occasionally in small boats but there's nowhere near as big of a media circus around him as Hvaldimir. Either way, if Hvaldimir were to be taken into human care for his own protection, it would have to be under guidance of experienced cetacean trainers and care experts (and not activists who refuse to cooperate with anyone who's ever touched a captive cetacean - as OneWhale is trying to accomplish - which is just mind boggling to me).

That’s good to hear! My concern for him is that he’s going to be hit by a boat—he’s already sustained injuries from a propellor. He clearly enjoys human company, and OneWhale certainly isn’t helping the situation by constantly interacting with him (and sharing pictures of him being petted and played with) while in the same breath telling others to leave him alone. Like you said, there’s no one on their “staff” with any experience caring for managed cetaceans.

I think the Beluga Whale Sanctuary would be a better option than building him his own pen, so he can learn to interact with other belugas again. They’re partnered with Whale & Dolphin Conservation, an anti-cap charity, but they’ve got people with actual relevant experience on their team (like Dr. Isabella Clegg, a PhD scientist specialized in captive cetacean welfare) and do what’s best for their whales even when it irritates activists (moving them to an indoor facility during the winter months). They’re one of the few technically anti-cap pages I follow since they focus on their animals instead of attacking other facilities. Not perfect of course, but worlds better than the Whale Sanctuary Project.

Even so, I doubt they’ll ever move him there since they’re too worried about him breeding Little White and Little Grey. And they’d never allow him to be taken to an aquarium.

#don’t get me started on onewhale #ANTI-CAPTIVITY in their bio but want to put him in a pen #whatever you call it that IS captivity #hvladimir #belugas #belugas whales #cetaceans #marine mammals #beluga whale sanctuary #answered asks #namu-the-orca

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csnews · 5 years

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Historic whale and dolphin stranding data made public for the first time

Josh Davis - March 28, 2019

Between 1913 and 1989, the coastguard, fishermen and members of the public sent the Museum their sightings of whale and dolphin strandings from around the UK coast. Now for the first time this data is being made public, allowing anyone to search the historic cetacean (whale, dolphin and porpoise) strandings records. Ellen Coombs is studying whale evolution for her PhD at the Museum, and has been delving into the strandings data to see what can be learnt from these historic records as part of a new scientific paper.

'It is one of the longest systematic cetacean stranding data sets in the world,' says Ellen.

Between 1913 and 1989, all records of stranded whales and dolphins on UK shores were sent to the Museum. Since 1990, the dedicated UK Cetacean Stranding Investigation Programme (CSIP), funded by the Department for Environment, Food and Rural Affairs, took over the recording of these data, although strandings can still be reported to the Museum. Around the same time, the Irish Whale and Dolphin Group was set up in Ireland to record cetacean strandings there.

In the 106 years represented by the full data set, there have been more than 20,000 reported strandings from 28 different species of cetacean. There are about 90 cetacean species in the world - so roughly a third of them have been spotted in UK waters. The majority of these strandings represent the most common species found in UK waters: the harbour porpoise, short-beaked common dolphin and long-finned pilot whale.

Yet the benefit of strandings records, as opposed to counting living whales and dolphins, is the opportunity to document rarer, shyer and more transient species that may be found around the country. Hidden among the records are some more unusual sightings, including some of the deepest-diving mammals in the world. Cuvier's beaked whale has been known to descend 2,992 metres for up to 137 minutes at a time. It's rarely sighted on the surface, but the species does keep cropping up in the stranding records.

Similarly, while there was a lot of excitement surrounding the appearance of Benny the beluga in the Thames estuary this winter, there are actually two other records of beluga washing ashore in the UK in 1932 and 2014, while in 1949 two narwhals stranded.

Recording whale extinctions

Researchers are able to use strandings data to track whale population numbers. Paradoxically, if more dead whales wash up on beaches, it is often a sign of a thriving population. If no cetaceans are spotted (even dead ones), it may indicate their numbers are struggling. One of the most poignant moments recorded in the data set is the loss of blue whales from around the British Isles. The largest animals ever to have lived, they once migrated through UK waters - until they were the target of intense hunting at the start of the twentieth century, which decimated their numbers.

The last blue whale to strand in the UK washed up in 1957, nine years before nations agreed on a global ban on hunting the cetaceans. But the blue whales were not alone in being targeted. Whalers concentrated on most of the large whale species, particularly baleen whales. These include more familiar species such as humpback and minke, but also sei and fin whales.

'There was a drop in baleen whale standings after the Second World War,' says Ellen. 'We speculate that this was because of a huge increase in post-war whaling and fishing to feed and fuel the starving population of Europe.

'We know that fishing and whaling increased in the 1950s, and we found that there were even a few years in this decade where we had no baleen whale standings at all. This downward trend continued into the 1960s as numbers of baleen whales remained low.'

In recent years the numbers of cetacean strandings being recorded have been on the rise. This might not sound like a good thing, but could be down to a number of positive factors. The first is simply that there are more people aware of the UK's marine life and recording what they find on the beaches. The ubiquitous use of smartphones means that not only are people more likely to positively identify what they find, they are also more likely to report it to the correct organisations.

It could also represent an increase in the overall numbers of cetaceans now living around the British Isles, although it is important to note that this is not easy to prove. There has been a corresponding increase in the number of whale and dolphin sightings in general, however.

Diving deeper

With this research, Ellen has only scratched the surface of what can be done with the data. 'The level of detail in the 20,000 records is mind-blowing, especially since 1990, when it started being recorded by CSIP,' explains Ellen. 'There is so much information in the data. The scope is just huge. In many of the modern records you get incredibly fine scale details for some specimens, such as testicle size.

'This means that the possibilities of what you could do with the data are incredible.' The data could be used to focus on a smaller time period or narrowed down to just a single species. This could then be compared to timings of military sonar exercises, for example, or levels of by-catch over the same period, potentially showing any relationships that may or may not exist between human activity and cetacean strandings.

The records also underscore the importance of the stranding network and the vital need to keep it funded. Not only does the data give insight into the presence and distribution of cetaceans, it can also help answer questions ranging from the parasitology of these animals to their relationship with their environment. 'It is very important for conservation around the UK, as you want to know where cetaceans are stranding and why,' explains Ellen. 'If all of a sudden a species disappears, it says a lot about the health of the oceans.'

#news #wild #cetacean #dolphin #whale #research #strandings

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2251bluewhales · 6 years

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Week 11

I’m. Done. With. My. Research. Synthesis.

And now I can comfortably sleep at night.

Before I go into that, I’d just like to mention that I went out on yet another field survey recently and we were graced by some beautiful humpback whales with spectacular coloration in the flukes. I think it might be time for another whale-inspired tattoo pretty soon.

Data entry isn’t as difficult as I thought it was going to be (*aggressively knocks on wood*). I think due to the generally slow behavior of humpback whales and the overall small number of animals present which allowed for us to comfortably keep an eye on every subject and note their behaviors and various environmental parameters.

Additionally we observed several species that are not of direct interest to us: California sea lions, and several harbor porpoises that made brief appearances throughout the day, including a calf that was probably small enough to fit in a backpack. Adorable.

I’m not angry or anything, but we also 100% missed out on killer whales and I might actually pop a blood vessel out of frustration having not seen them for several years now.

The research synthesis essentially took the paper Familial Social Structure and Genetic Differentiation in Hawaiian Short-Finned Pilot Whales (Van Cise et al., 2017) and broke down the study into layman’s terms. As I had mentioned previously, apparently I know a lot less about genetics than I thought I did (not that my initial scope of knowledge was by any means expansive or impressive, but nonetheless, it was a bit of an explosive reality check).

I’ll try my best to sum up the study in short, seeing as my research synthesis was an extensive 19 pages long [including a laundry list of citations].

Based on photo-ID surveys and previous studies by Cascadia Research Collective, short-finned pilot whales in Hawaii are divided into three communities, each favoring specific regions: the Main Hawaiian Islands population, the North Western Hawaiian Islands population, and the Pelagic population. The study aimed to determine if social structure and genetic structure were related.

254 samples were taken from adult whales by way of biopsy darts, arrows that are shot at the whale (typically along the back below the dorsal fin) and designed to remove small portions of flesh. These skin samples were processed and the DNA extracted, and from those samples 112 individual whales were genotyped within the three communities.

It was found that these whales exhibit very little genetic variation (specifically referring to diversity in the mitochondrial DNA haplotypes) within the communities, BUT the Main Hawaiian Islands community was found to be genetically distinct from the North Western Hawaiian Islands and Pelagic communities. Furthermore, photograph-ID projects show that the Main Hawaiian Islands community is divided into two distinct subgroups which also exhibit genetic differentiation, the Eastern and Western Main Hawaiian Island communities. More research and a larger sample size is necessary to truly understand the dynamics of gene flow and characterize the genetic structure of Hawaiian short-finned pilot whales. For now, the study concludes that relatedness of individuals affects their social structure, and that animals that were closely related were much more likely to associate with one another. Likewise, the social structure of these animals has affected their genetic structure despite overlapping ranges. As the whales differentiate into social clusters composed of related families, evidence now supports the hypothesis that family units of pilot whales within a cluster were once larger groups that have since separated, likely due to the death of a common ancestor, thus are more likely to associate with one another (similar to killer whales). However, the lack of gene flow between these social clusters suggests socially learned breeding restrictions, including inbreeding avoidance behavior within the communities. The question now remains, which of these social clusters are encouraging gene flow, and who are they breeding with? It goes without saying that more research is needed.

Of course, breaking down every little step of the procedure and extrapolating the results, as well as identifying gaps and error sources and the prospects for future studies, took more than a simple summary.

While most of the information falling into the realm of advanced genetics (so like... all of it...) is completely new to me, some of the more interesting factoids I learned are as follows:

You can hybridize DNA of species that have not been genotyped (in this case, short-finned pilot whales), with the DNA of closely related species to fill in gaps within the DNA strand. This process is called “enriching”, and bottlenose dolphin DNA was used to enrich the structure of the harvested pilot whale DNA, and used to successfully genotype the individual whales identified in the study

Animals in the Pelagic population shared common haplotypes (a group of genes inherited from the mother) with pilot whales from SE Asia, the South Pacific, the Indian Ocean.

Animals in the North Western Hawaiian Islands population shared a common haplotype with the Main Hawaiian Islands population (identified as haplotype J) which suggests the occurrence of gene flow between the communities. However, the North Western population also possessed a haplotype unique to the community, which would suggest the North Western population is diverging from the Main Hawaiian Islands population. A larger sample size is necessary to test this hypothesis.

Little else is known about the ecological and social behaviors of these pilot whales, but a better understanding of their movements, social structures, dietary preference, breeding strategies, and vocal repertoires may reveal the divergence of these communities into distinct ecotypes, possibly even promoting speciation as in the case with orca populations.

I would be absolutely thrilled to participate in such studies on pilot whales in the future. I come to a personal hurdle of finding out who would be responsible for taking care of the ever-growing collection of exotic reptiles I have at home (which are prohibited in the state of Hawaii), but I’m sure I could weasel my way into an annual field survey one of these summers, given of course Cascadia would allow me to return for round two next summer and potentially allow me to work alongside or with them directly in the future.

As I always say, we’ll cross that bridge when we get there. Now excuse me while I pass out and sleep for the next two days.

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eco-nnect · 3 years

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The majority of the 470 pilot whales stranded on a sandbank in Tasmania have died

Mass strandings of pilot whales in Australian waters have been happening for the last decade. The reason why remains unknown to scientists. In 1996, 320 pilot whales washed ashore in Western Australia and in 2017 600 pilot whales beached in nearby New Zealand. This week’s 470 pilot whale strand in Macquarie Harbour, Tasmania would be Australia’s largest whale beaching in modern history.

Volunteers and rescuers have been working tirelessly in the cold waters. The refloating process involves as many as five people per whale wading waist-deep in freezing water, attaching slings to the animals so they can be guided out of the harbour by a boat. About 50 whales have been rescued this way, however there is a high likelihood that they will return, creating an exhausting loop for rescuers. During the NZ stranding in 2017 rescuers created a human chain to block the freed whales from returning.

After two days of a difficult and dangerous rescue attempt, state marine scientists said at least 380 of the long-finned pilot whales have died. Now the rescuers are looking into putting different plans in motion on what to do with the carcasses.

What are pilot whales and how do they behave?

Despite the misleading name, the long-finned pilot whale is actually a large dolphin—reaching up to four and six meters in length and weighing up to one tonne. They migrate through vast areas of the Southern Antarctic Ocean, using echolocation to navigate the complete darkness and to hunt for squid (echolocation uses the reflection of sound to find objects).

In order to fully understand mass strandings, one must realise the emotional complexity of whales and dolphin species, as well as their bond and loyalty to the pod as a whole. The bond is so strong and communal that as humans we can barely grasp it. An example of their emotional depth was documented when a pilot whale was seen carrying its dead calf for many days. Similarly, killer whales have showed strong social bonds within their pods, to the point that if a close member strands others will attempt to join in order to die together—which can explain why a liberated whale returns to the beached pod.

However, the mystery remains on the exact reason why. Here are some theories:

Theory 1: Whales are very social creatures, always travelling in large pods. Sometimes, the leader whale can get confused and she might lead the rest of the pod to the shoreline, causing them to all strand together in solidarity. Theory 2: A change in the sea environment has lead them closer and closer to the shorelines, perhaps in search of food, like squid. Climate change shifts ocean currents as sea temperature rises—and with this squid availability is changing. Theory 3: Changes in electromagnetic fields that disorient them when they are using echolocation are causing them to reach the shore. This change in the field can be caused by naval sonars and deep sea mining. Sources: BBC, Reuters, The Conversation

#tasmania #pilotwhales #2020Q5

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wwasnorkel · 4 years

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Types of Whales in Hawaii

Whale watching in Hawaii is one of the top rate activities. Every year thousands of humpback whales migrate to Hawaii from Alaska during winter months, making their stay in Hawaii seasonal. But there are other whales that grace the waters of Hawaii year-round!

Humpback Whales

Maui’s most popular whale residents are the humpback whales. As we mentioned, they are seasonal inhabitants, but they return every year to mate, give-birth and enjoy the warm tropical waters.

Although the humpback whales can be found in Oahu, Big Island, Kauai and outer islands, they are most populated in the Maui Nui Basin which is settled between Maui, Kaho-olawe, Lanai and Molokai, It is fairly shallow and offers reef areas that act as safe nurseries for mother humpback whales giving birth or with their young. Humpback whales are a type of baleen whale, the largest mammals on earth and there are more than a dozen species of them! They are called baleen whales because they have baleen, a fringe like filter in their mouth used to capture small fish and plankton for food! Another characteristic that differentiates baleen whales from toothed whales is a pair of blowholes they have (other types of whales only have a single blowhole). Humpback whales are also known for their large pectoral fins and fluke (or tail) markings that are unique to every humpback whale.

Humpback whales can weigh 30-50 tons—that’s 60,000 to 100,000 lbs! Female humpbacks are actually larger than males, ranging from 49-52ft, whereas adult males are 43-46 ft long, the size of a school bus! Humpback whales live to an average of 50 years, and don’t have many predators, except the Orca (killer whale) that preys on young humpback whales.

Humpback whales engage in many surface behaviors including breaching, spyhopping, pec and tail slapping; these are used to communicate with each other. They also sing beautiful songs, which we can hear when we place a hydrophone into the water! This song is sung solely by male humpback whales, but mom and calf pairs use quiet vocal noise to communicate with each other during migration.

Although the humpback whale population is one-third of its original population, the protections that have been put in place have helped the population begin to recover and we see more baby humpback whales every year! You have an excellent chance of seeing Humpback whales in Hawaii if you visit during the migration months of December through April!

Killer Whales

The humpback whale’s top predator, the majestic Orca or Killer Whale, is rarely seen, but has been spotted around the Hawaii island chain. Although their name calls them whales, Orcas are actually a part of the Delphinidae family, also known as oceanic dolphins. Orcas are found across the globe, but most reside in colder waters of the Antarctic, Norway and Alaska. Transient killer whales find their way to Hawaii, but stay far from shore, living in pods of 20 or more animals and using underwater sounds to communicate with each other. Killer whales are also mammals, ranging between 20-30 feet in length with a distinct black and white color and sharply shaped dorsal fin. Orcas feed on small mammals including other whale calves and can live up to 90 years old! They are known for their fierce hunting and intelligence. Although spotting these whales while visiting Hawaii is rare, keep on the lookout, you never know what you may see!

False Killer Whales

Also known as pseudo-orcas, false killer whales are apex predators, feeding off large pelagic fish and other marine life. Although false killer whales got their name because of their similar skull shape to their flashy name sharing cousins, they are distinctly different, solid black or dark grey in color and smaller in size. These mammals are very social and are known to spend time with other members of the dolphin family. There are three groups of pseudo orcas in Hawaii, but they do not interact with each other: The pelagic population, the Northwestern Hawaiian Islands populations and the Hawaiian Islands insular population that is currently endangered. There are specific locations around the Hawaiian Island chain where these pods spend most of their time. We have observed them several times during our snorkel and whale watching tours in Maui.

Blue Whales

Blue whales are one of the rarest whales to be seen in Hawaii, and most confirmations are not sightings but sound recordings of their songs (their call is the loudest animal sound in the world) around the islands throughout the year. Blue whales are endangered and were targeted by commercial whalers in the 1900’s, there are estimated to be only 10,000- 25,000 globally, which is less than 10% of the population that was present in the early 1900. The blue whale population is steadily growing every year since we have reduced commercial whaling. These whales are so large ( about 80 feet long and up to 300,000 lbs) there are no natural predators to adult blue whales (except humans), giving them long life expectancies of 100 year. One of the coolest facts about blue whales is that their hearts are 5 feet long, their babies are born 26 feet long and gain 200 lbs a day feeding on their mother’s milk.

Although the only recorded sighting of blue whales in Hawaii was in the 1960’s we still keep our eyes opened for these massive blue giants.

Other Whales (and toothed-whales)

Melon-headed whales, Blainville and Cuvier’s Beaked whales, Pygmy Killer whales, Dwarf Sperm whales, Short-finned pilot whales and Sperm whales are also present in Hawaii. Many live offshore so sightings are rare and because they are rare most of us wouldn’t even know how to identify them! They vary in sizes, colors and population, but all need our protection and support.

Respect and research help us protect these amazing whales and dolphins in Hawaii! Every ticket with Ultimate Whale Watch and Snorkel helps us support marine research groups like Whale Trust, Keiki Kohola, Cascadia, SCRIPPS, Hamer, NOAA, UH and many more that spend time gaining information on our whales and dolphins in Hawaii and how our ocean environment affects them. We also work as first responders with NOAA’s whale entanglement response team to respond to whales which may be entangled with fishing line, nets or other hindrances. NOAA’s team has successfully disentangled 97 whales since the 1990s and continues to research, educate and protect Maui’s marine life.

Want to learn how to better support Maui’s marine research? Contact us!

#humpback whales #Whale Watching #Hawaii #Maui #Lahaina #types of whales

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ezatluba · 5 years

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Measuring stress hormones in big whales such as this humpback is extraordinarily difficult, so scientists were excited to discover a record of whales' hormone levels in their earwax.

Earwax reveals how humans have changed whales’ lives

Hormones in earwax reveal how human activities, from whaling to war, have been stressing out whales for more than a century and a half.

BY CHRISTIE WILCOX

NOVEMBER 15, 2018

HUMAN EARWAX, WHETHER removed by a curious finger or an ill-advised cotton swab, is usually tossed in the nearest garbage shortly after its removal. But this sticky substance can hang on to clues about health that build up in the ear canal over time—including in the giant ears of whales.

Luckily, museum curators around the world have had the good sense to hold onto massive plugs of earwax pulled from dead whales over the centuries.

Thanks to those plugs, scientists have now discovered a record, hidden in earwax, of how human activities have stressed out whales over the past century and a half. Stephen Trumble, a comparative physiologist at Baylor University, and his colleagues published the findings this month in Nature Communications.

It turns out we’re incredibly stress-inducing—from whaling to war to climate change, our actions have been affecting whales, even if we don’t interact with them directly.

Waxy Records

Each earwax plug, which can be more than a foot and a half long (50 centimeters) and weigh two pounds (about a kilogram), contains a wealth of information about the environmental conditions the animal lived in, as well as the health of the whale itself over its lifespan.

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And because the wax is added in layers—similar to tree rings—researchers can get a time series of data on everything from pesticide contamination to reproductive cycles.

But it was the animals’ response to human activities that Trumble and his colleagues were especially keen to examine. And one of the best ways to do that is to measure the levels of hormones such as cortisol that are released when an animal is stressed.

A southern right whale encounters a diver on the sandy sea bottom off the Auckland Islands, New Zealand. Adults can reach lengths of 55 feet and weigh up to 60 tons.

Humpback whales were hunted to near extinction, with numbers dropping by more than 90 percent before a 1966 ban allowed the species to bounce back.

A group of narwal gather en masse at an Arctic ice floe to eat cod. The animal's tusk is actually a tooth that can grow more than nine feet long; it has baffled people for centuries.

Also known as white whales, belugas (pictured, an animal at St. Lawrence Marine Park in Quebec) live in the Arctic. Calves are born gray or even brown and only fade to white as they become sexually mature around five years of age.

Pilot whales swim off Kona, Hawaii. Oceanic whitetip sharks sometimes follow pods of these whales, possibly eating scraps of prey left behind.

An orca, also known as a killer whale, herds herring into a tight group near Andenes, Norway. Largest of the dolphins, this predator also feasts on marine mammals such as seals, sea lions, and even whales.

Belugas communicate with echolocation, a built-in sonar that allows them to sense objects nearby. They do this via their melon, a fatty organ in the center of their forehead that gives the skull its distinctive shape.

The narwhal’s iconic tusk is actually a repurposed canine tooth. This complex sensory organ transmits stimuli from ocean water to the brain.

Intensely social creatures, orcas hunt in pods, family groups of up to 40 individuals. The species can be found from the polar regions to the Equator.

Minke feed near the surface of Cashes Ledge, a rich region of marine biodiversity within the Gulf of Maine. This species is still hunted: In 2016, Japanese whalers killed 333 minke whales—including more than 200 pregnant females.

The bowhead, which lives in chilly northern waters, can live up to 200 years. A cold environment causes a low body temperature, which in turn means slow metabolism—and thus less damage to tissues.

Like the orca, the long-finned pilot whale is a large dolphin that forms family pods. The highly social species earned its moniker from their tendency to follow a leader, or "pilot," during lengthy migrations.

Sperm whales (pictured off the Azores) were intensely hunted for a fatty substance in their heads, called spermaceti in their heads, used as an oil and lubricant in the 1800s.

Humpback whales (pictured, an animal near Antarctica) emit moans, howls, cries, and other complex noises that can continue for hours. The 1979 "Songs of the Humpback Whale" album made the animals' "songs" famous.

Obtaining long-term data on whale hormone levels is incredibly difficult. It’s basically impossible to track and sample from individual animals over their entire lifetime. A whale’s baleen, which it uses to filter food, contains roughly 10 years of information, but the animals can live for 50 to 100 years, so that’s just a glimpse at their life.

Their earwax plugs, on the other hand, provide decades of data.

Extracting such information, however, is no small feat, says Trumble. Separating layers of wax for analysis—each of which contains information from approximately six months of the whale’s life—takes days of careful work.

But the result is worth it. “Being able to put together a picture of what stressors are involved and then the response of the whale—especially over lifetimes—is unprecedented,” says Trumble.

Nick Kellar, a cetacean biologist with the NOAA’s Southwest Fisheries Science Center in La Jolla, California, agrees. “This represents the best available science on the non-lethal effects of whaling and is a major advancement in this field,” he says.

Fin whale populations were hit hard by whaling in the 20th century, and the animals are still targeted by whalers despite being endangered.

War and Global Warming

In the new study, hormone profiles from 20 fin, humpback, and blue whales revealed a tight connection between whaling activities and stress from the late 19th century to the 1970s, when legislation dramatically reduced the hunting of whales.

“The result that surprised us was the correlation itself,” says Trumble. While the researchers expected whaling to increase stress, they didn’t expect hormone levels to drop in lock-step with reductions to hunts. “These whales truly mirror their environment and can be used in a way similar to the canary in the coal mine,” he adds.

Hunting wasn’t the only source of stress that the researchers saw, either. From 1939 to 1945, elevated cortisol levels indicated that the whales’ stress levels were high, even though fewer whales were being harpooned. But there was another stressor at the time: global war. “We suspect this increase in cortisol during World War II is probably a result of noise from planes, bombs, ships, et cetera,” says Trumble.

After about 1970—and especially after 1990— the researchers saw a worrying trend: Cortisol levels also increased rapidly alongside rising water temperatures. This suggests that climate change, too, is stressing the whales.

There are lots of ways that increased temperatures could affect the animals—from altering the location and abundance of prey to direct effects on their physiology from hotter waters (after all, it’s not like whales can flip on the air conditioning when their homes get uncomfortably warm). Trumble says he and his colleagues are still trying to narrow down exactly what about climate change is causing the increase in stress.

That will require more research, since the connection to temperature is based on plugs from just six whales. In addition, Kellar says that he’d like to see other variables such as the animal’s cause of death taken into account, as the natural aging process can affect hormone levels.

That doesn’t mean there’s no climate connection, though. “The weaknesses in the study are merely a reflection of inherent difficulties of trying to address an historic question at this scale,” Kellar says.

The best way to suss this all out would be to study more earwax plugs—and luckily enough, that’s exactly what Trumble is planning. They’ve got dozens to analyze, he says. “Stay tuned.”

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myenchantingcollectorpaperp-blog · 6 years

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Monterey Gulf Whale Check Out Trips.

Today our team experienced a varied series of Azorean sea life. Monterey Gulf draws in such a great quantity and also selection of aquatic lifestyle due to the upwelling that draws the cool, nutrient-rich waters up from the submarine canyon. -- Coconut oil has actually been actually raising in popularity for many years as well as is actually right now understood for its large health and wellness benefits.

There are actually 10 types from baleen whales. The façade is actually and reveals scriptural scenes peopled with daily life sized sculptures of kids, birds and also creatures. This is why many locations like the Wolf Preservation Facility use 'emissary creatures' to teach younger creations regarding the mistreatment from specific species. A Florida adolescent just recently created titles when he made a decision to hitch a spontaneous, unbelievable ride on the back of a 50,000-pound whale shark. There is actually an entire host from tasks accessible - including exceptional whale as well as dolphin watching, a genuinely exciting geographical record excursion, going for a swim with dolphins, bird observing, diving, golf, off-road jeep trips, walking as well as bicycling are all possible. Teaming Up the Study Group on Emissions, Modelling as well as Climate Modification, he was involved in much more than 30 International ventures and over 800 clinical magazines on environmental influence evaluation, air high quality administration, wind passage simulations, visibility to atmospherical toxins and human health, temperature change relief and also naturalization, investigation and also technology for round economic condition, sustainable progression. Dolphins as well as other cetaceans are actually understood to become several of the 'most intelligent' creatures on the planet near humans, in addition to elephants, primates, and also corvids (the 'crow' family), nonetheless, in spite of the presence from no effective documentation, many individuals think that they are practically as intelligent, as intelligent, or perhaps smarter than people. Reacting to http://www.polishcreatives.pl/chocolate-slim-polska-opinie-z-forum/ from viewer frustration, Breakthrough provided a claim Monday defending its promotion for the series, emphasizing that this performed certainly not mislead audiences in to believing that Phelps was dashing a real terrific white. A Dry Spot is any kind of molecular, uninhabited (non-breathing) non-living, brief tool, things, material that monsters can journey with in order to get to a long-term bunch body. Most of the world's rapidly growing areas remain in low-income nations where utilities and authorities could possess restricted capability to prepare for and control urban expansion and its own impacts on water and also energy requirement. Whales are the wonderful sign and truth of a healthy and balanced sea. A Whale Watching Cruise ship could transform your entire viewpoint on life - this could touch the deepest of emotions - bewilder you with affection as well as devotion - possess you experience all warm and comfortable as well as fuzzy - as well as this is actually all at the sight of among the absolute most amazing mammals on this world - The Humpback Whale. Dolphins and whales may strand all together - most lately, ten long-finned pilot whales ended up being stranded on a coastline near Calais, 7 which perished - however we can not identify a solitary reason that this happens. Fishes likewise shows up in the cinematic mobster idiom copulate the fishes, made use of to indicate that a person has been whacked (and also probably given a water burial). Alongside observing the whales, you could additionally observe dolphins, turtles, and, if you are blessed, a whale shark. Whale Whales are actually larger and possess a baleen, a sieve like construct that filterings system the little fish that they consume, coming from water. That many dolphins defy ethical ideas is actually certainly not evidence au contraire, more compared to our a lot of immoral as well as amoral human beings are documentation that humans can easily not comprehend morality.

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catalinachamber · 6 years

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A Snapshot of Wildlife on Catalina Island

Catalina Island hosts a wide array of animals, ranging from majestic bison to diminutive foxes and from massive blue whales to agile dolphins. On land, sky and sea, these creatures thrill visitors, contribute to the island’s heritage and are part of the unique fabric that forges the environment of Santa Catalina Island.

On the land

Catalina’s terrestrial wildlife includes several introduced species as well as fascinating native creatures found nowhere else on earth. One of the most iconic Catalina animals was brought to the island for a film shoot in the 1920s. North American Bison – popularly known as buffalo – were shipped to the island in anticipation of them making a grand appearance on the silver screen. Although the scenes with the bison landed on the cutting room floor, the bison on the island thrived, becoming so much a part of the landscape – and the Catalina culture – that their future here is assured.

Bison on Catalina are found on logos, restaurant names, souvenirs and countless postcards. They also make two appearances on menus – as buffalo milks and bison burgers.

The Buffalo Milk cocktail first made an appearance at Two Harbors in the 1970s, but their deceptive deliciousness assured that the drink quickly became an island favorite that every bartender on Catalina knows how to make. The frothy concoction includes bananas, Kahlua, vodka, crème de cacao and crème de bananas – no milking of buffalo required.

Bison meat — high in protein, low in fat and with a much lighter hoof print on the environment than beef — has become a popular alterative around the country and Catalina is no exception. Frequently described as slightly sweeter than beef, bison meat has been embraced by burger fans and environmentalists alike. The Catalina Bison Burger Trail showcases those restaurants that serve their own variation of bison burgers, providing a new opportunity to sample this beef alternative while experiencing a wide range of restaurants.

Seeing actual bison on Catalina Island is as easy as getting out of town. North American bison, which are honored on the first Saturday of November on National Bison Day, can be seen on an interior tour, while hiking the TransCatalina Trail and while camping at several Catalina Island campgrounds.

Catalina Island bison share their home with two other grazers that have been introduced by humans long before we realized that bringing non-native species to a new environment was a bad idea. Mule deer were introduced in the 1920s in the hopes of creating a draw for hunters. Since then, the prolific animals have thrived on the island. Visitors and locals alike frequently see them in Avalon, where they snack on landscaping and are nearly tame. Indian blackbuck antelope, another exotic species brought over as an experiment in hunting, survives in a very small – and rarely seen — population near the Airport the Sky.

Catalina’s native mammals, while not as large, are equally as fascinating. Catalina Island fox, slightly smaller than a housecat, are the largest native mammal. Having recently been removed from the Endangered Species List, these endearing canids are now often seen throughout the island, particularly at dawn and dusk, when they are most active. Native foxes are accompanied by squirrels, mice and shrews as native Catalina Island mammals.

In the sky

Nearly 200 species of birds have been spotted on the island, making Catalina a popular destination for birders hoping to add to their life lists. Birds on Catalina are particularly diverse, due to the wide range of environments – shorebirds, raptors and grassland species all make their year-round homes here and a large number of bird species make Catalina a stop on their annual migrations.

Two of the most intriguing birds on Catalina include both one of the island’s largest species and its smallest. Thanks to an intensive re-introduction campaign, bald eagles once again soar free over the island. The USA’s national bird is frequently spotted by visitors along the island’s coastline and popular webcams provide an intimate look at the majestic birds as they rear their chicks. On other end of the spectrum are hummingbirds – Catalina is home to two species, Allen’s and Anna’s – which are found throughout the island, particularly in Avalon, where they find decorative flowers and bird feeders irresistible.

Spotting one of Catalina’s other native bird species requires a trip to the interior. A subspecies of quail native to the Southern California mainland, the Catalina Island quail is a ground-dwelling species about the size of a pigeon. With their distinctive grey coloring and black topknot, Catalina Island quail are an exciting sight off the beaten path in the Catalina Island interior.

In Avalon, Catalina’s visitors frequently get an up close and personal look at a variety of birds of prey, thanks to an innovative program to control the pigeon population. On The Wing Falconry uses these impressive avian predators to make Avalon less hospitable to pigeons. The aerial acrobatics of hawks and falcons are on display several times a week, swooping low along the pier or soaring over the heads of surprised visitors on Crescent Avenue.

In the sea

Catalina wildlife is frequently spotted even before arriving on the island. Dolphins and whales are regularly seen from the ferry to Catalina, thrilling visitors and locals alike.

The most common dolphin seen is, well, the common dolphin. These gregarious and athletic mammals congregate in massive pods that can include up to thousands of animals. Leaping from the sea, they frolic from both the bow and the stern of the Catalina ferry, inspiring awe and “ahhs.” Much larger than their “common” cousins, Pacific bottlenose dolphins are also frequently spotted on the ferry to Catalina as well as on dolphin tours that leave from Avalon. Risso’s dolphins, pilot whales and orcas can also be spotted during a Catalina crossing.

Catalina Island whale watching can be equally as rewarding. From November to March, California gray whales pass the island on their annual migration – the longest of any mammal. Wintering in the warm lagoons off Baja and summering in the nutrient-rich waters off Alaska, the great mammals are a frequent sight from the Catalina ferry when the migration is underway.

In the summer months, the largest creature on the planet is regularly seen in the waters around the island. Growing up to 100 feet, blue whales dwarf even the largest dinosaurs and in July and August these behemoths cruise around the island, inspiring wonder wherever they are seen.

Mammals aren’t the only ocean residents that intrigue visitors to the island. Each spring, flying fish arrive, shooting from the waves in long-distance leaps to avoid predators. The unique finned flyers have become part of the culture of Catalina, appearing on postcards and taking center stage on a number of tours.

The post A Snapshot of Wildlife on Catalina Island appeared first on Catalina Island.

from Catalina Island http://ift.tt/2hNlEHq via IFTTT

#IFTTT #Catalina Island

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adamcairnsorg-blog · 7 years

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The Reptile Within: How Our Brain Structure Influences Behaviour

A Perfectly Evolved Structure?

Our brains control almost everything we do but have you ever wondered how the brain is constructed, what evolutionary forces shaped it? People sometimes ask whether a decision is governed by the head (brain) or the heart (emotion) but as we will see this is probably a false distinction. It might be better to think of our decisions as emerging from a soup of neural connections blending basic insticitive fight or flight mechanisms with our higher cognitive activity.

Can we be certain that our decisions are governed by a rational evaluation of all of the evidence? Or is it more likely that we are frequently flying along, swerving this way and that based on what our gut instinct advises?

The Hungry Brain

The brain of the average human being weighs between 1.2kg and 1.4kg about 2% of total weight. This complex organ controls most of our bodily functions, interprets the world around us, stores memories, creates interpretation and meaning, dreams, thinks, feels and establish personality.

It is a hungry organ and feeds greedily on blood glucose, but will if necessary get by for a time on ketones or lactates.

It consumes:

15% of the heart’s output

20% of total body oxygen consumption

25% of total body glucose utilisation.

The brain of a Homo Sapiens today is 40% larger than the first humans, Homo Habilis but has been shrinking over the last 28,000 years. The brain of Homo sapiens neanderthalensis, the branch of humanity we call neanderthal, had a brain 11% larger than our own.

This phenomena of reducing brain size, the result of opposing evolutionary forces, led scientists to develop the notion:

“As large as you need and as small as you can”.

In other words our brain is small but perfectly formed.

Our Matryoshka Doll 3 Brain System

The brain we have today is actually a composite made from three separate systems.

Reptile Brain

The oldest brain lies deepest inside the structure and is sometimes referred to as the housekeeping brain. It is similar in structure to the brains of reptiles and birds and so is also known as the “R-Complex” where “R” stands for reptilian.

The reptilian brain is responsible for controlling our basic functions: hunger, temperature control, fight-or-flight fear responses, defending territory, keeping safe.

The reptilian brain is our most primitive brain.

Limbic Brain

As animals became more complex additional structures began to surround the old reptilian formation. Eventually the reptilian brain was wholly surrounded, encased in a shell or “girdle” of additional brain structures.

The latin for arc or girdle is “limbus” and so this structure is known as the “limbic system”.

We share this brain type with otherolder mammals like dogs, cats, cows and horses. The limbic system is responsible for emotions like rage, fear, disgust and surprise.

Neocortex Brain

Finally as mammals evolved into even more sophisticated animals like chimpanzees, dolphins and humans, the brain developed a top layer called the cortex or neocortex.

This system is responsible for all of the brain’s higher functions like planning, and complex social interactions including language.

Humans possess a composite brain therefore which is made up of three individual systems which have evolved from primitive to complex.

Interestingly, while there is assumed to be an association between the relative size of the neocortex and intelligence, scientists discovered in 2015 that a species of whale, the long-finned pilot whale has the most neocortical neurons of any mammal so far studied.

Implications For You And Me

Our brains evolved sequentially, a bit like a coral reef. One layer was deposited on another and because the direction of evolution was "upward", it means that the connections made between each brain system also work most effectively in an upward direction. Our neocortex is able to receive a signal from both of the older systems extremely rapidly. Unfortunately, the connections are relatively weak heading downward from neocortex through the lambic brain and onto the reptile brain.

Why does this matter?

It matters because our conscious, rational self receives signals from our more primitive brains very fast. These arrive perhaps as a strong "gut reaction" or emotional response. Our neocortex then attempts to "explain" these signals to use. Very often this is after we have already reacted intinctively.

Sadly, it is also the case the our neocortex is also very adept at post hoc rationalisation: finding explanations and justifications for our reactions. We might believe we are responding with cool, rational precision when in fact we are merely providing cover for our instinctive response.

Disgust and Fear

Ever wonder why you don't like spiders, or snakes or the taste of food that has gone off? Fear (snakes, spiders) and disgust (tainted food) are all primitive reactions that have a sound evolutionary foundation. However disgust can spill over into areas where it might not belong. Demonising sections of the population and "dehumanizing" them so it is permissible to feel disgust at the "contamination" caused by these groups is a long-standing historical phenomena.

The question is, how can we prevent these impulses from driving us in directions we don't really want to go?

Here are two strategies for dealing with the implications of this brain structure.

Develop a mindfulness practice: One of the key benefits of a mindfulness practice is that it eventually becomes second nature to observe the train of thought as it passes across your mind. By developing this impartial and compassionate observation of the mind's activities, we can create a moment's pause between the thought and the response. Useful if the "thought" is actually a rationalisation for an emotional reaction to something.

Keep a journal: Journaling regularly has many benefits. Recording what happens during the day and in particular what went well and what you can improve upon allows us to develop a more reflective attitude. Over time we can recognise patters of behaviour we are prone to and this can help us to avoid making responses we would rather not.

Question: How do you manage your instinctive reaction to events?

#Mindset

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csnews · 5 years

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New sub-species of pilot whale identified in Pacific Ocean

Woods Hole Oceanographic Institution - June 3, 2019

Short-finned pilot whales are found over a wide swath of the world's oceans, with habitats in the Indian, and Pacific, and North Atlantic oceans. Despite this wide distribution, the whales have been recognized as a single species—but a recent study has found that two unique subspecies actually exist. The study published June 3, 2019, in Molecular Ecology.

Japanese whalers and scientists have long described two "forms" of short-finned pilot whales with distinct body types—the 'Naisa' form, which live in Southern Japan and have square-shaped heads; and the 'Shiho' form, which lives in northern Japan and have round heads. Yet no prior study had examined the genetic diversity of those whales on a global scale, says Amy Van Cise, a postdoctoral scholar at WHOI and lead author on the study.

"You can't manage animals globally without understanding their diversity. If you think of a group of animals as a single species, and it turns out they're not, you could wind up accidentally losing an entire subspecies without knowing it," she says.

Van Cise was able to study the entire global population structure of the whales using marine mammal tissue archived at NOAA's Southwest Fisheries Science Center. From it, she identified more than 700 samples taken from short-finned pilot whales, and extracted DNA from each one.

After analyzing the DNA, Van Cise found that there are actually two distinct subspecies of short-finned pilot whale. Surprisingly, she says, those subspecies aren't separated by any continental barrier, but instead by the vast expanse of the eastern Pacific Ocean.

"You would expect to see a different subspecies of whale in each ocean basin—the Atlantic, Indian, and Pacific. That's pretty common. But what we found was that short-finned pilot whales in the Atlantic are the same sub-species as those living in the Indian Ocean and western Pacific," she says. Whales living off northern Japan and the eastern Pacific, however, seemed to be a single distinct subspecies.

From an evolutionary perspective, adds Van Cise, the study shows that the enormous central region of the Pacific—an area with little productivity or food to support the whales—formed a major barrier to the whales' global distribution.

"It seems to have separated these groups of whales for long enough that they diverged into two different types," she says. "That means continents and land forms may not have been as significant a barrier as we thought to this species' evolution. Instead, the oceanic 'desert' in the Pacific might have been more important."

To test these findings, Van Cise used a small section of the whales' mitochondrial DNA (mtDNA) to determine each group's genetic divergence (how much its genetic code differed from the others). By comparing that divergence with known whales and dolphins, she was able to verify if the groups were unique species, subspecies, or populations.

"mtDNA is a pretty standard way to look at population structure in a species. It's really abundant in tissue, and it's much easier to sequence than nuclear DNA. It only has 16,300 base pairs as opposed to a few million." Because it's relatively easy to sequence, scientists have been able to look at a short portion of the mtDNA in whales and dolphins to identify distinct species. With that powerful genetic database, they can identify previously overlooked species or subspecies with tissue samples rather than relying on observing body shape—a more traditional approach that is often slower and more expensive to accomplish.

#news #wild #cetacean #whale #dolphin #pilot whale #research

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