Killer Whales are a type of Dolphin

[Senegoid]

@Really_Not_All_That_Bright

I’m so confused. Are we actually debating whether killer whales are dolphins? I thought that was pretty much settled. Are we also going to debate whether they’re mammals?

Well, one of the side-debates here is whether killer whales are actually, y’know, killers. People-killers, that is.

[Senegoid]

ETA:
There seems to be room for a lot of euphemism here. I’ve read several books (the type that tries to argue how cutesy lovable cuddly dolphins are, including killer whales), which try to dispel the notion that orcas are dangerous. An oft-repeated argument: They are known to kill much larger whales, even blue whales, by wolf-packing them and are thus whale killers. This phrase has been mangled into being killer whales. :dubious:

Also:
It was questioned above whether wild dolphins, generally being non-aggressive toward people, are being friendly or simply leery. I’m pretty sure leery is the correct answer, most of the time anyway. By all the accounts I’ve read, they are mostly rather timid about people, keeping their distance. Captive dolphins, of course, generally become very tame very quickly.

The stories you read about friendly wild dolphins are apparently outlier cases. Several have become well-known, but those clearly seem to be the exceptions rather than the rule. I’ve read it speculated that these may actually be outcast dolphins (for whatever reason) that are lonely and craving some kind of social interaction, which they find they can get with humans.

[Grotonian]

Is there any speculation as to why orcas don’t eat us? I can’t get past the fact that they easily could and choose not to. There has to be a reason, right? How are they not like sharks where attacks are rare, but still occur?

Is it really that they “know” we’re intelligent? Is there something gross in our digestive tracts or stomachs that they verbally tell each new generation is poisonous? I just don’t understand how they’ll eat literally any other large mammal (elk, moose, polar bears, sea lions, seals, walrus) but we humans ALWAYS get a free pass? WHY?

[John_Mace]

@Grotonian

Is there any speculation as to why orcas don’t eat us? I can’t get past the fact that they easily could and choose not to. There has to be a reason, right? How are they not like sharks where attacks are rare, but still occur?

There are a lot more sharks than orcas.

[Grotonian]

@John_Mace

There are a lot more sharks than orcas.

Right, but your response suggests it’s just a matter of time. But the account of the 12-year-old who was bumped suggests an orca will NEVER attack a human. Why didn’t these six hungry orcas EAT this fucking kid?

http://www.seattletimes.com/seattle-news/boy-survives-bump-from-killer-whale/

[Senegoid]

I went to a week-long symposium in at University of Washington, Seattle, all about orcas. (It was in 1980, just a few weeks after Mt. St. Helens blew up. The airplane flew right over it, and we all got to look out the windows right down into the crater, which was still smoking.) It combined scientific speakers with artistic orca-themed speakers. One of them had done expeditions where one of them went swimming among orca pods in the area, while others on the boat videotaped it. The videos were shown at the conference.

Nobody got eaten.

But one audience member (one of the speakers of the scientific persuasion, I think) stood up and strongly protested how irresponsible and reckless he thought it was to make and show such a video, which he felt would encourage miscellaneous other people to dive in and go swimming with wild orcas.

[Irishman]

@Darwin_s_Finch

This sort of thinking is true if one ascribes to a gradistic form of classification, but not for a cladistic one; or, to put it another way, if you group things based on how they look rather than their evolutionary history.

Also, humans aren’t described as “reptiles” under a cladistic scheme, because nowadays Reptilia is effectively synonymous with Sauropsida; humans are members of Synapsida, which is the sister clade of Sauropsida within Amniota.

But even under that system, birds are reptiles. Wikipedia again:

Despite the early proposals for replacing the paraphyletic Reptilia with a monophyletic Sauropsida which includes birds, that term was never adopted widely or, when it was, applied consistently.[16] When Sauropsida was used, it often had the same content or even the same definition as Reptilia. In 1988 Jacques Gauthier proposed a cladistic definition of Reptilia as a monophyletic node-based crown group containing turtles, lizards and snakes, crocodilians, and birds, their common ancestor and all its descendants. Because the actual relationship of turtles to other reptiles was not yet well understood at this time, Gauthier’s definition came to be considered inadequate.[16] A variety of other definitions were proposed by other scientists in the years following Gauthier’s paper. The first such new definition, which attempted to adhere to the standards of the PhyloCode, was published by Modesto and Anderson in 2004. Modesto and Anderson reviewed the many previous definitions and proposed a modified definition, which they intended to retain most traditional content of the group while keeping it stable and monophyletic. They defined Reptilia as all amniotes closer to Lacerta agilis and Crocodylus niloticus than to Homo sapiens. This stem-based definition is equivalent to the more common definition of Sauropsida, which Modesto and Anderson synonymized with Reptilia, since the latter is more well known and more frequently used. Unlike most previous definitions of Reptilia, however, Modesto and Anderson’s definition includes birds,[16] as there is no other way to establish a monophyletic clade that includes both lizards and crocodiles.

Which would still make humans “amphibians”, and we would be fish, except scientists have decided we can’t be fish, so the term “fish” is paraphyletic and not used as a true cladistic classification. Isn’t that the same thing - excluding tetrapods from “fish” because of appearance? Why is that valid?

@Darwin_s_Finch

Under a cladistic scheme, to deny that birds are dinosaurs or humans are monkeys is an arbitrary (and false) denial. Would you deny that humans are mammals? Would you deny that humans are primates? Would you deny that humans are haplorrhin primates? If the answer is to any of those questions is no, then why would you deny that they are therefore also monkeys? Similarly, birds are ornithuran maniraptoran coelurosaurian theropod dinosaurs, so there’s no non-arbitrary reason to deny them their dinosaur-hood.

I suppose that’s a fair point. It does lend confusion to the layperson, who thinks of dinosaurs as those scary lizard monsters from the past, and birds as the feathered flyers (and a few non-flyers) of the present.

Thinking about it some more, classic dinosaurs lasted for 135 Million years, compared to the mere 66 million years that mammals have been on the scene. In that time, mammals have diversified from tree-shrew-like varmits to everything from monkeys to elephants, blue whales to porpoises, bats to cats to armadillos, kangaroos, porcupines, and even platypuses. I guess if we allow mammals that much diversity, it’s not ridiculous to think that dinosaurs could have developed and changed a fair amount during their reign, and that birds aren’t that far different than bats are to monkeys.

I guess the real challenge is wrapping our collective heads (i.e. all the various non biologists) around the concept of cladistic grouping. I’m okay considering humans as monkeys in the sense that our ancestors were monkeys, the same way I’m okay considering us apes and mammals. It’s a bit difficult considering us amphibians, and calling us “fish” is a bit silly.

But if someone said “imagine a monkey”, my first thought is not of a human. It’s some tailed furry mammal that eats bananas and lives in trees. It’s all about context.

And thanks for the correction on shark evolution. They’re still significantly different than modern bony fish. Hell, they don’t even have scales like fish - they have denticles, which are teeth. (That’s right - sharks are covered in teeth.)

@Really_Not_All_That_Bright

I’m so confused. Are we actually debating whether killer whales are dolphins? I thought that was pretty much settled. Are we also going to debate whether they’re mammals?

Well, the person who was arguing that killer whales are not dolphins (and also arguing that dolphins were really porpoises and not dolphins) didn’t show up in this thread, so the argument was won by forfeit.

@John_Mace

There are a lot more sharks than orcas.

It’s still historically known that orcas do not tend to attack and certainly don’t eat humans. The Tlingit culture of the American northwest has a creation story that explains why orcas don’t attack humans. If it was established well enough that this Native American culture created their religious lore around the idea, that is some level of historical evidence to support the notion.

Similarly, plenty of humans surf in the coast off California, where there are plenty of orcas. Yet we only have 1 story of an orca attack on a surfer, and it was aborted. That was over 30 years ago.

We have a more recent incident where an orca broke off an attack on a boy when it realized it wasn’t a seal. I watched a Nat Geo program on killer whales that filmed a killer whale cornering a seal in a small bay in a similar style attack.

Here are orcas not eating kayakers. Okay, they’re in boats, you say.

Here’s swimming with wild orcas and not getting eaten. Starts around 1:20. These orcas don’t seem leery at all.

Here’s one titled “Orcas chase surfers out of the water!” Except that’s not what I see. I see orcas hunting seals, and seals swimming towards shore to get away from orcas, and surfers deciding that they might not want to be where orcas are hunting seals, especially while wearing wetsuits so they look like seals. But the orcas don’t seem to go near any of the surfers.

There are plenty of human/orca interactions in the wild for attacks to occur if they were probable. Plenty of humans deliberately putting themselves in front of orcas. Yet only 1 documented bite in over 30 years.

Even the documented attacks by captive orcas, the orcas don’t eat the humans. The worst have been mauled a bit, but no missing parts. Usually they’re drowned and/or crushed.

[Boyo_Jim]

The last one, the third kill by the same whale, was partially eaten. There is some audio that is in the documentary where a withness tell an emergency responder that the woman was dragged around by the arm, and the repy is “Where’s the arm now?” followed by “swallowed”.

[Darwin_s_Finch]

@Irishman

But even under that system, birds are reptiles.

Well, yes, but there I was talking about humans, not birds.

Which would still make humans “amphibians”, and we would be fish, except scientists have decided we can’t be fish, so the term “fish” is paraphyletic and not used as a true cladistic classification. Isn’t that the same thing - excluding tetrapods from “fish” because of appearance? Why is that valid?

“Amphibians” are basically any non-amniote tetrapod, so humans would not be included. We are members of Sarcopterygii, though the designation of that group as “fleshy-finned fish” is more of a hold-over from Linnaeus’ more gradistic classification. Better to simply call us (and our relatives) “sarcopterygians”. “Fish” remains a largely gradistic class of animals which look like, well, fish.

I suppose that’s a fair point. It does lend confusion to the layperson, who thinks of dinosaurs as those scary lizard monsters from the past, and birds as the feathered flyers (and a few non-flyers) of the present.

However, as time goes on and the science filters down to the layperson, it becomes more common to see such notions as outdated. Consider, for example, the kids cartoon Dinosaur Train, wherein dinosaurs are presented (more or less, for a cartoon) based on current scientific info. They even have an episode wherein it is explained that not all Mesozoic animals were dinosaurs (an idea of which many older folks still have some difficulty letting go). Ever since Jurassic Park, people seem to be more open to birds and dinosaurs being closely related.

Thinking about it some more, classic dinosaurs lasted for 135 Million years, compared to the mere 66 million years that mammals have been on the scene.

Dinosaurs and mammals both appeared on the scene at around the same time (dinosaurs first appeared roughly 231 million years ago, while the earliest mammal appears around 210 mya). Granted, mammals weren’t nearly as diverse then as they became in the post K-Pg world, but they were present, and not all of them were ratty /shrewy things.

In that time, mammals have diversified from tree-shrew-like varmits to everything from monkeys to elephants, blue whales to porpoises, bats to cats to armadillos, kangaroos, porcupines, and even platypuses. I guess if we allow mammals that much diversity, it’s not ridiculous to think that dinosaurs could have developed and changed a fair amount during their reign, and that birds aren’t that far different than bats are to monkeys.

Indeed!

I guess the real challenge is wrapping our collective heads (i.e. all the various non biologists) around the concept of cladistic grouping. I’m okay considering humans as monkeys in the sense that our ancestors were monkeys, the same way I’m okay considering us apes and mammals. It’s a bit difficult considering us amphibians, and calling us “fish” is a bit silly.

Well, as noted above, the last sentence isn’t strictly true; we’re definitely not amphibians, and we’re only “fish” in a colloquial sense. We are, however, amniote tetrapod sarcopterygian therapsids

And thanks for the correction on shark evolution.

It wasn’t really a correction; I was just clarifying your two uses of the word “bony”, since it might might have been a but confusing to some (“they evolved from bony fish before there were bony fish”).

[Skammer]

Has the commonly accepted classification of dolphins v. porpoises changed in the last couple of decades, by chance?

The reason I ask is that back in the early '90s I worked for time at the Shedd Aquarium in Chicago and saw the marine mammal show more times than I could count. They featured Pacific white-sided dolphins, beluga whales, and (for a brief period) a couple of Pseudorcas (false killer whales). I remember clearly the part of the presentation where the marine biologist was talking about the animals and would say “People always ask us, ‘what’s the difference between a dolphin and a porpoise?’ There is no difference.” They would then explain that dolphins, porpoises and toothed whales were all Cetaceans (or something) and that the belugas (a toothed whale) were more closely related to the dolphins than to baleen whales.

[Darwin_s_Finch]

As near as I can tell, Phocoenidae (porpoises) has existed as distinct from Delphinidae (dolphins) since 1825, when John Edward Gray first erected the group (interestingly, he also created Delphinidae, in 1821; indeed, he’s responsible for erecting or redefining most of the "families’ within Odontoceti, between 1821 and 1846).

[Grotonian]

@Irishman

It’s still historically known that orcas do not tend to attack and certainly don’t eat humans.

I know. But WHY NOT??? I understand that it may not be known to a certainty, but some of you must have better guesses than I do. How do six hungry, HUNTING orcas not eat the 12-year-old? Or at least bite a chunk out of his ass? I am already convinced that orcas DO NOT see us as prey. But what I’m losing sleep over is WHY NOT?

[Senegoid]

Professional courtesy?

[Boyo_Jim]

They need jobs – maybe gigs at Sea World are a big prize to them.

[Slow_Moving_Vehicle]

@Colibri

Once upon a time, pedants would scold people for calling apes monkeys. Now it turns out that apes actually are monkeys.*

*It used to be thought that apes were a distinct branch of the primate family tree from Old and New World Monkeys. Now it turns out that apes are more closely related to Old World Monkeys than either is to New World Monkeys, so it’s OK to call apes monkeys,

Fine. But you tell the Librarian.

@Irishman

If you don’t go out of your way to be a dick, wild dolphins seem reasonably friendly towards humans - curious enough to check us out when they find us swimming around, not typically attacking or acting aggressive.

They do however kill porpoises (Phocoenidae) and infant dolphins. As I pointed out in another thread, referring to chimps, humans, and dolphins, intelligence seems to correlate with cruelty.

@Captain_Amazing

Bah! And trout are more closely related to people than either are to sharks, but trout are fish, and sharks are fish, but people aren’t fish. To hell with cladistics.

So do we get to burn the witch or not?

[sisu]

So is Pluto still not a planet?

[Yllaria]

@Left_Hand_of_Dorkness

I’ll have a much easier time accepting that orcas are leery of humans than accepting that they’re friendly toward humans. Why on earth would they treat humans as anything other than calorie sources or dangers?

Well there’s at least one documented case of orcas herding large whales into a bay for humans to kill. PowerPoint here.

There are many instances of various species of dolphins running fish into human nets. Maybe the word’s gotten around.

I found one article that claimed that orcas are picky eaters.

[Grotonian]

@Yllaria

Well there’s at least one documented case of orcas herding large whales into a bay for humans to kill. PowerPoint here.

There are many instances of various species of dolphins running fish into human nets. Maybe the word’s gotten around.

I found one article that claimed that orcas are picky eaters.

The Two-Fold Bay account is fascinating. That makes sense that those Orcas helped men, they benefitted from the kill. But why don’t orcas eat humans in California? I would think that except for all the silicone, those Los Angelenos would be delicious.

[Irishman]

@Grotonian

I know. But WHY NOT??? I understand that it may not be known to a certainty, but some of you must have better guesses than I do. How do six hungry, HUNTING orcas not eat the 12-year-old? Or at least bite a chunk out of his ass? I am already convinced that orcas DO NOT see us as prey. But what I’m losing sleep over is WHY NOT?

I am actually curious for an answer, too. My response was directed at John Mace’s proposed explanation that it is a numbers game, so I was pointing out significant numbers exist to show a pattern.

Looking through the wikipedia pages, there is one documented case were a polar explorer was taken from the ice in the late 1800s. Possibly confused for a seal? That is about the only solid case of apparent predation recorded. Several others show possibly hunting dogs, or thinking the dogs are seals.

No one seems to know. Speculation that they recognize us as mammals, but that seems unlikely as orcas will prey on dolphins and dolphins will prey on porpoises.

@sisu

So is Pluto still not a planet?

Well, you see, Pluto is not a “planet”, it’s a “dwarf planet”. :smack: Currently still not a planet, because then we’d have to include Eris and Sedna and Quaoar - three other icy bodies in the outer solar system that are bigger than Pluto.

@Grotonian

The Two-Fold Bay account is fascinating. That makes sense that those Orcas helped men, they benefitted from the kill. But why don’t orcas eat humans in California? I would think that except for all the silicone, those Los Angelenos would be delicious.

It’s even more complicated than that. I was watching a Nat Geo program discussing orca predation on white sharks, and the orca specialist was discussing the orca populations off the American West coast. There are three distinct populations. One population lives further from shore, they remain all seagoing or around islands, and prey primarily on fish. A second population live near shore and prey primarily on seals, with some fish hunting. Then there’s a third population that lives around San Fransisco but travels up and down the coast and further from shore than the shore bound group. This is the population documented preying on a white shark. They are visually distinct by having barnacles, which shows they spend time in warmer waters further south, like by Mexico, and they all show much more scarring and damage to their sides and fins. It was proposed that this population learned to prey on white sharks because they spend time in warmer waters with less abundant sea life, and it’s a white shark nursery in the Gulf of Baja. Less abundant sea life means looking for more variety in diet.

So why don’t these orcas eat humans? They eat seals, fish, and great white sharks, but not surfers off the California coast or fishermen off Mexico.

[Irishman]

@Boyo_Jim

The last one, the third kill by the same whale, was partially eaten. There is some audio that is in the documentary where a withness tell an emergency responder that the woman was dragged around by the arm, and the repy is “Where’s the arm now?” followed by “swallowed”.

Okay.

@Darwin_s_Finch

“Amphibians” are basically any non-amniote tetrapod, so humans would not be included. We are members of Sarcopterygii, though the designation of that group as “fleshy-finned fish” is more of a hold-over from Linnaeus’ more gradistic classification. Better to simply call us (and our relatives) “sarcopterygians”. “Fish” remains a largely gradistic class of animals which look like, well, fish.

Okay, this is partially a matter of unclear presentation on wikipedia and partially my fault for relying so heavily on wikipedia. From Timeline of human evolution:

Acanthostega is an extinct amphibian, among the first animals to have recognizable limbs. It is a candidate for being one of the first vertebrates to be capable of coming onto land. It lacked wrists, and was generally poorly adapted for life on land. The limbs could not support the animal’s weight. Acanthostega had both lungs and gills, also indicating it was a link between lobe-finned fish and terrestrial vertebrates.

Ichthyostega is an early tetrapod. Being one of the first animals with legs, arms, and finger bones, Ichthyostega is seen as a hybrid between a fish and an amphibian. Ichthyostega had legs but its limbs probably weren’t used for walking. They may have spent very brief periods out of water and would have used their legs to paw their way through the mud.[12]

[snip]
Shortly after the appearance of the first reptiles, two branches split off. One branch is the Sauropsids, from which come the modern reptiles and birds. The other branch is Synapsida, from which come modern mammals. Both had temporal fenestrae, a pair of holes in their skulls behind the eyes, which were used to increase the space for jaw muscles. Synapsids had one opening on each side, while diapsids had two.

The earliest mammal-like reptiles are the pelycosaurs. The pelycosaurs were the first animals to have temporal fenestrae. Pelycosaurs are not therapsids but soon they gave rise to them. The Therapsida were the direct ancestor of mammals.

Can you see how that says that the link between fish and mammals goes through amphibians, and how Synapsida is a branch of reptiles? Of course, terms keep getting redefined, which makes it hard to follow.

Dinosaurs and mammals both appeared on the scene at around the same time (dinosaurs first appeared roughly 231 million years ago, while the earliest mammal appears around 210 mya). Granted, mammals weren’t nearly as diverse then as they became in the post K-Pg world, but they were present, and not all of them were ratty /shrewy things.

I hate being wrong so many times, especially in a thread I started to correct someone else’s mistakes.

@Skammer

Has the commonly accepted classification of dolphins v. porpoises changed in the last couple of decades, by chance?

The reason I ask is that back in the early '90s I worked for time at the Shedd Aquarium in Chicago and saw the marine mammal show more times than I could count. They featured Pacific white-sided dolphins, beluga whales, and (for a brief period) a couple of Pseudorcas (false killer whales). I remember clearly the part of the presentation where the marine biologist was talking about the animals and would say “People always ask us, ‘what’s the difference between a dolphin and a porpoise?’ There is no difference.” They would then explain that dolphins, porpoises and toothed whales were all Cetaceans (or something) and that the belugas (a toothed whale) were more closely related to the dolphins than to baleen whales.

Perhaps this is a case of [del]lies told to children[/del] context? Dolphins, porpoises, and toothed whales are all Cetaceans - i.e. whales. Toothed whales are a subgrouping that includes belugas and sperm whales as well as the dolphin family and the porpoise family. Orcas are part of the dolphin family.