# Killer Whales are a type of Dolphin **URL:** \ **Category:** Great Debates\ **Created:** [March 21, 2015, 2:26am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564 "2015-03-21T02:26:43Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 22, 2015, 12:37am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/21 "2015-03-22T00:37:08Z")
> [@Trinopus](#): > > Well, there ya go. I’d been told, in a thread much like this one (entirely different BBS) that they weren’t! > > I not only have fallen for folk taxonomy, but for folk debunking! > > (I just did a quick search, and found the adviso, “Scientists no longer believe that giant pandas are more like raccoons than bears.” I hadn’t been paying attention, and missed that memo!) Once upon a time, Giant Pandas were bears. When I was growing up, they were raccoons. Now they are back to being bears again.😃 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, ---
**Author:** ![Captain\_Amazing](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@Captain\_Amazing](https://boards.straightdope.com/u/Captain_Amazing)\ **Post date:** [March 22, 2015, 1:21am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/22 "2015-03-22T01:21:43Z")
> [@Colibri](#): > > \*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, 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. 🙂 ---
**Author:** ![dasmoocher](https://avatars.discourse-cdn.com/v4/letter/d/dbc845/32.png) [@dasmoocher](https://boards.straightdope.com/u/dasmoocher)\ **Post date:** [March 22, 2015, 1:32am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/23 "2015-03-22T01:32:06Z")
> [@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. 🙂 George Costanza: The sea was angry that day, my friends - like an old man trying to send back soup in a deli. I got about fifty feet out and suddenly the great beast appeared before me. I tell you he was ten stories high if he was a foot. As if sensing my presence, he let out a great bellow. I said, “Easy, big fella!” And then, as I watched him struggling, I realized that something was obstructing its breathing. From where I was standing, I could see directly into the eye of the great fish. [mine] Jerry Seinfeld: Mammal. George Costanza: Whatever. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [March 22, 2015, 2:23am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/24 "2015-03-22T02:23:31Z")
> [@Captain\_Amazing](#): > > but people aren’t fish. I know a few flounders. ---
**Author:** ![Captain\_Amazing](https://avatars.discourse-cdn.com/v4/letter/c/6de8d8/32.png) [@Captain\_Amazing](https://boards.straightdope.com/u/Captain_Amazing)\ **Post date:** [March 22, 2015, 3:50am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/25 "2015-03-22T03:50:52Z")
Which leads us to the conclusion that whales ARE fish after all. ---
**Author:** ![buddy431](https://avatars.discourse-cdn.com/v4/letter/b/6a8cbe/32.png) [@buddy431](https://boards.straightdope.com/u/buddy431)\ **Post date:** [March 22, 2015, 6:21am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/26 "2015-03-22T06:21:20Z")
> [@Captain\_Amazing](#): > > Which leads us to the conclusion that whales ARE fish after all. That’s fine by me. I mean, all it really does is illustrate how useless of a definition a “fish” is: “All aquatic vertebrates, with some exceptions” is as about as good as you can get. ---
**Author:** ![DagNation](https://avatars.discourse-cdn.com/v4/letter/d/ee7513/32.png) [@DagNation](https://boards.straightdope.com/u/DagNation)\ **Post date:** [March 23, 2015, 6:01am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/27 "2015-03-23T06:01:40Z")
I remember being taught that there are 2 kinds of whales - baleen and toothed, and that dolphins are a part of the toothed branch. I have never heard it phrased as “killer whales are dolphins” though. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [March 23, 2015, 8:19am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/28 "2015-03-23T08:19:04Z")
> [@DagNation](#): > > I remember being taught that there are 2 kinds of whales - baleen and toothed, and that dolphins are a part of the toothed branch. I have never heard it phrased as “killer whales are dolphins” though. Sperm whales have teeth. I never heard of them being called dolphins either. ---
**Author:** ![Freudian\_Slit](https://avatars.discourse-cdn.com/v4/letter/f/5daacb/32.png) [@Freudian\_Slit](https://boards.straightdope.com/u/Freudian_Slit)\ **Post date:** [March 23, 2015, 11:31am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/29 "2015-03-23T11:31:43Z")
> [@Senegoid](#): > > Sperm whales have teeth. I never heard of them being called dolphins either. They’re not. It’s not that all toothed whales=dolphins. Just that killer whales happen to be in the dolphin family. ---
**Author:** ![Broomstick](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/broomstick/32/246_2.png) [@Broomstick](https://boards.straightdope.com/u/Broomstick)\ **Post date:** [March 23, 2015, 12:14pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/30 "2015-03-23T12:14:30Z")
> [@](#): > > I might also point out that, in all the many years mankind has interacted with dolphins (porpoises, actually), there has never been evenoneverified attack on a human by a porpoise. That alone should tell us something. > [@](#): > > That is not true. At least, not WRT dolphins, don’t know about porpoises. > [@](#): > > I stand corrected.Oneincident. On the other hand, if a bunch of people were trying to jam sticks upyournose, wouldn’t you be a little irritable? All the other damages can be attributed to excessive playfulness and a porpoise’s innate practical joker mentality. In the book _Behind the Dolphin’s Smile_ by Richard O’Barry he relates an incident where a captive dolphin mangled a woman’s arm… admittedly, it was an animal that had been mistreated and neglected for years and was pretty hostile towards everyone. Can’t give page numbers as I no longer own the book, but it does do a lot to tear down the notion that dolphins are these wonderful, friendly, inherently playful creatures. They’re wild animals. I expect there have been attacks on humans, but they probably weren’t documented. And if you don’t know who Richard O’Barry is – he’s the guy who did the animal training for the TV show _Flipper_, as well as several other projects. ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [March 25, 2015, 8:52am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/31 "2015-03-25T08:52:36Z")
> [@Trinopus](#): > > Until this thread, I might have agreed. There is such a thing as “folk taxonomy,” and it tends to vary from academic taxonomy. It wasn’t so much that she was wrong, it was the utter certainty combined with the air of authority that bugged me. > [@](#): > > There are people who think Pandas are “Bears.” Shrug. Folk taxonomy is a little like intuitive physics: it’s wrong, but worth studying, to understand why it is so compelling. (Who among us has not thought that the path of an object thrown from a spinning carousel is curved? It feels like it.) > [@John\_Mace](#): > > Pandas are bears. Were you thinking of Koalas (or red pandas)? > [@Trinopus](#): > > Well, there ya go. I’d been told, in a thread much like this one (entirely different BBS) that they weren’t! > > I not only have fallen for folk taxonomy, but for folk debunking! > > (I just did a quick search, and found the adviso, “Scientists no longer believe that giant pandas are more like raccoons than bears.” I hadn’t been paying attention, and missed that memo!) Checking [wikipedia](http://en.wikipedia.org/wiki/Giant_panda): > [@](#): > > **Classification** > For many decades, the precise taxonomic classification of the giant panda was under debate because it shares characteristics with both bears and raccoons.[59] However, molecular studies suggest the giant panda is a true bear and part of the family Ursidae,[3][60] though it differentiated early in history from the main ursine stock. The giant panda’s closest extant relative is the spectacled bear of South America.[61] The giant panda has been referred to as a living fossil.[62] > > Despite the shared name, habitat type, and diet, as well as a unique enlarged bone called the _pseudo thumb_ (which helps them grip the bamboo shoots they eat) the giant panda and red panda are only distantly related. Molecular studies have placed the red panda in its own family Ailuridae, and not under Ursidae. Despite morphological similarities, extensive DNA studies have lead scientists to classify [red panda](http://en.wikipedia.org/wiki/Ailuridae)s as a separate Family, not a subfamily within the raccoon family. > [@buddy431](#): > > That’s fine by me. I mean, all it really does is illustrate how useless of a definition a “fish” is: “All aquatic vertebrates, with some exceptions” is as about as good as you can get. I believe this gets into the nature of folk etymologies that **Trinopus** mentions. Words like “monkey” and “fish” and “dinosaur” and even “planet” originated long before there was a systematic attempt at understanding classification and interrelatedness of the various types. Everything that swims in the ocean is a fish. That means “starfish” and “jellyfish” are called those things because they’re “fish” in that sense. So whales are “fish” and so are sharks. And then someone comes along and says, “No, whales are _mammals_, they _can’t_ be fish.” And then scientists get all busy trying to sort and shuffle and make the existing terms make sense, but they can’t really because the terms include things that don’t really fit. Us laypeople get attached to words having certain meanings. Scientists muck around with those words to try to shoehorn them into a system that works from a science perspective, but it grates on the nerves and the sensibilities of the people who grew up thinking Pluto is a planet and sharks are fish. The alternative can also be confusing. Looking at human ancestry, for example, and some people argue that “humans did not descend from monkeys, monkeys and humans descended from a common anscestor”, leaving out the detail of what that common ancestor was. Looking at the [family tree](http://en.wikipedia.org/wiki/Timeline_of_human_evolution), one of those ancestors appears to be [Aegyptopithecus](http://en.wikipedia.org/wiki/Aegyptopithecus). Here is what wikipedia states: > [@](#): > > _ **Aegyptopithecus** _, which means “Egyptian Monkey”, from Greek Αίγυπτος (Egypt) and πίθηκος (ape or monkey), is an early fossil anthropoid that predates the divergence between hominoids (apes and humans) and cercopithecids (Old World monkeys). It is known from a single species, _ **Aegyptopithecus zeuxis** _, which lived some 35-33 million years ago in the early part of the Oligocene epoch. It likely resembled modern-day New World monkeys (it is about the same size as a modern howler monkey, which is about 56 to 92 cm (22 to 36 in) long). Looking at that picture, I defy you to tell me why that is not a “monkey”. No, it is not any of the currently extant species of monkey, but it is still a monkey. I also don’t think it’s fair to call humans “monkeys” or fair to call birds “dinosaurs”. It doesn’t make any more sense than calling humans “reptiles” because we descended from Synapsids, or calling us fish because way back in our ancestry there was a gilled swimmer. Humans have changed sufficiently that those terms are not accurate. Birds have changed sufficiently that “dinosaur” is not accurate. Sure, it’s neat to know that not all dinosaurs died out, that they kinda morphed into something else instead. But that’s not quite the same thing. I’m sure I’m going to get heaped on for that last one. > [@Broomstick](#): > > In the book _Behind the Dolphin’s Smile_ by Richard O’Barry he relates an incident where a captive dolphin mangled a woman’s arm… admittedly, it was an animal that had been mistreated and neglected for years and was pretty hostile towards everyone. Can’t give page numbers as I no longer own the book, but it does do a lot to tear down the notion that dolphins are these wonderful, friendly, inherently playful creatures. They’re wild animals. While I agree with the conclusion that they are wild animals and are more than the stereotype we’ve been given by pop culture, I don’t think that one example is especially illuminating or representative. Take a prisoner of war who was daily beaten and tortured and starved and brainwashed for several years and then newly free him, he’s not going to necessarily be very friendly to be around. Doesn’t mean humans by nature are as testy and untrusting as that guy. > [@](#): > > I expect there have been attacks on humans, but they probably weren’t documented. It’s possible. There’s a comedy bit about how dolphins have this reputation for saving distressed swimmers and whatnot, but it’s an act. We don’t hear about the cases when nobody else is around, and the dolphins decide to eat the person. But if there’s other people around, they play nice and blame the sharks. I’m not as adamant as **MIchelleRose** , but I find it intriguing that there are so few known incidents of even Killer Whale attacks on humans. You’d think surfers, who are reasonably frequently attacked by sharks, might have more cases of mistaken identity to report. So far, we’ve got 1 surfer bitten in 1974. Worldwide. 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. ---
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [March 25, 2015, 8:10pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/32 "2015-03-25T20:10:55Z")
> [@Irishman](#): > > . . . Looking at that picture, I defy you to tell me why that is not a “monkey”. No, it is not any of the currently extant species of monkey, but it is still a monkey. > > I also don’t think it’s fair to call humans “monkeys” or fair to call birds “dinosaurs”. It doesn’t make any more sense than calling humans “reptiles” because we descended from Synapsids, or calling us fish because way back in our ancestry there was a gilled swimmer. Humans have changed sufficiently that those terms are not accurate. Birds have changed sufficiently that “dinosaur” is not accurate. Sure, it’s neat to know that not all dinosaurs died out, that they kinda morphed into something else instead. But that’s not quite the same thing. > > I’m sure I’m going to get heaped on for that last one. . . . Not by me: I agree with everything you said. I admit, I like cladistics as a taxonomic strategy, because it can be closer to absolute and objective. You can’t put Zebras in a different group than horses, because there are things we call “horses” branching off both before and after Zebras. Cladistics fans are really pissy about that. But even this isn’t totally absolute, and it also messes up some of the comfortable old classifications. There are also (I’ve read somewhere) contradictions between fossil cladistics and DNA clock cladistics, so, clearly, we need to have more work done in calibrating. But, yeah, that thiny sure looks like a monkey! ---
**Author:** ![John\_Mace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/john_mace/32/185_2.png) [@John\_Mace](https://boards.straightdope.com/u/John_Mace)\ **Post date:** [March 25, 2015, 8:18pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/33 "2015-03-25T20:18:45Z")
> [@Irishman](#): > > The alternative can also be confusing. Looking at human ancestry, for example, and some people argue that “humans did not descend from monkeys, monkeys and humans descended from a common anscestor”, leaving out the detail of what that common ancestor was. I don’t think many people say that. The last common ancestor between monkeys and humans was almost certainly a monkey, and would be classified as an (extinct) species of monkey by scientists. What you DO hear people say is something like: If humans evolved from monkeys, how come there are still monkeys around today? Which betrays a lack of understanding of how evolution works. ---
**Author:** ![Bone](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bone/32/407_2.png) [@Bone](https://boards.straightdope.com/u/Bone)\ **Post date:** [March 25, 2015, 8:33pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/34 "2015-03-25T20:33:41Z")
_head explodes_ So, are sharks actually fish? I think the answer is yes but everything is now out of order. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [March 25, 2015, 8:48pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/35 "2015-03-25T20:48:04Z")
> [@Bone](#): > > _head explodes_ > > So, are sharks actually fish? I think the answer is yes but everything is now out of order. Cartilaginous "fishes’ arent really very closely related to “bony” fishes (Osteichthyes). So no. However, due to the same environment and many times the same niche, the two look a great deal alike in many cases. So yes. But even way back in the _Systema Naturae_ old Linnaeus had “Pisces” being the Bony fish, and the sharks etc were sent off to that garbage can lumping of _Amphibia_, with the frogs, lizards, snakes and lampreys. So, the answer is either “yes or no”: they are both a \*paraphyletic group of organisms \*, so “yes”… But that’s not very useful. Scientifically, they have pretty much gotten rid of the term “fish” for taxonomy. So then “no”. ---
**Author:** ![Irishman](https://avatars.discourse-cdn.com/v4/letter/i/b487fb/32.png) [@Irishman](https://boards.straightdope.com/u/Irishman)\ **Post date:** [March 28, 2015, 9:05am UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/36 "2015-03-28T09:05:36Z")
> [@John\_Mace](#): > > I don’t think many people say that. I’ve have people say that on this board. Trying to correct me when I said humans descended from monkeys. “No, they descended from the last common anscestor between humans and monkeys.” Of course, look up wikipedia on [monkeys](http://en.wikipedia.org/wiki/Monkey). > [@](#): > > There are two major types of monkey: New World monkeys (platyrrhines) from South and Central America and Old World monkeys (catarrhines of the superfamily Cercopithecoidea) from Africa and Asia. Hominoid apes (gibbons, orangutans, gorillas, chimpanzees, and humans), which all lack tails, are also catarrhines but are not considered monkeys.[3] [snip] Because Old World monkeys are more closely related to hominoid apes than to New World monkeys, yet the term “monkey” excludes these closer relatives, monkeys are referred to as a paraphyletic group. Look at the family tree under Classification. It shows how apes are excluded from “monkeys”, but “monkey” covers the two sub groups under Simiiformes (simians). Looking back at _Aegyptopithecus_, it is classified under “Haplorhini”, which is one step back from Semiiformes, and includes Tarsiiformes (Tarsiers), which are _not_ monkeys. However, given that humans (and all apes) descended under Semiiformes, and Simians are monkeys, I would say we descended from monkeys - just not any of the extant monkey species. Similarly, there is confusion over the term “[ape](http://en.wikipedia.org/wiki/Ape)”. It appears some people use it as a synonym for gorillas, and humans are not descended from gorillas. However, we are apes - the common ancestor of gorillas and humans was an ape. Unless “ape” is paraphyletic, and means “all Hominoidea except for Homo sapiens” or some such. Different biologists have used it differently. > [@Bone](#): > > _head explodes_ > > So, are sharks actually fish? I think the answer is yes but everything is now out of order. To try to rephrase what **DrDeth** said… The things we most readily identify as “fish” are the bony, finned fish like trout and golfish and swordfish and bass and catfish, etc. They have a bony skeleton, bony fins, gills. Amphibians and reptiles and mammals and birds are all descended from bony finned fish. Sharks are not bony - they are all cartilage. They are closely related to rays and skates, also cartilaginous. Their ancestry diverges from bony fish earlier in the timeline before bony fish. Humans, being descended from bony fish, are more closely related to fish than sharks are. But sharks look like bony fish, with a similar body plan of bilateral symmetry, streamlined body, gills, fins, tail. Whales also look like fish, with similar features, sans gills. Scientists decided that since whales are mammals, they can’t be fish, except of course all mammals are descended from fish, but then calling them fish would confuse things. Laypeople still call things like crayfish and starfish and jellyfish “fish”, but they aren’t bony fish, they are different phylums than bony fish. Quick definitions to make the below more easily understood: A _monophyletic_ clade (group of organisims) is labeled such because that clade contains all the descendants of one common ancestor. “Mammals” are monophyletic. A _paraphyletic_ clade is a group where one or more descendant lines from that common ancestor are excluded from the group. Reptiles are paraphyletic, because they include all descendants from a common ancestor except for mammals and birds. Here is what [wikipedia](http://en.wikipedia.org/wiki/Fish) says: > [@](#): > > A fish is any member of a paraphyletic group of organisms that consist of all gill-bearing aquatic craniate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups. [snip] > > Because the term “fish” is defined negatively, and excludes the tetrapods (i.e., the amphibians, reptiles, birds and mammals) which descend from within the same ancestry, it is paraphyletic, and is not considered a proper grouping in systematic biology. The traditional term pisces (also ichthyes) is considered a typological, but not a phylogenetic classification. > [@](#): > > Unlike groupings such as birds or mammals, fish are not a single clade but a paraphyletic collection of taxa, including hagfishes, lampreys, sharks and rays, ray-finned fish, coelacanths, and lungfish.[13][14] Indeed, lungfish and coelacanths are closer relatives of tetrapods (such as mammals, birds, amphibians, etc.) than of other fish such as ray-finned fish or sharks, so the last common ancestor of all fish is also an ancestor to tetrapods. As paraphyletic groups are no longer recognised in modern systematic biology, the use of the term “fish” as a biological group must be avoided. > > Many types of aquatic animals commonly referred to as “fish” are not fish in the sense given above; examples include shellfish, cuttlefish, starfish, crayfish and jellyfish. In earlier times, even biologists did not make a distinction – sixteenth century natural historians classified also seals, whales, amphibians, crocodiles, even hippopotamuses, as well as a host of aquatic invertebrates, as fish.[15] However, according the definition above, all mammals, including cetaceans like whales and dolphins, are not fish. In some contexts, especially in aquaculture, the true fish are referred to as finfish (or fin fish) to distinguish them from these other animals. ---
**Author:** ![Darwins\_Finch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darwins_finch/32/20304_2.png) [@Darwins\_Finch](https://boards.straightdope.com/u/Darwins_Finch)\ **Post date:** [March 28, 2015, 4:54pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/37 "2015-03-28T16:54:08Z")
> [@Irishman](#): > > I also don’t think it’s fair to call humans “monkeys” or fair to call birds “dinosaurs”. It doesn’t make any more sense than calling humans “reptiles” because we descended from Synapsids, or calling us fish because way back in our ancestry there was a gilled swimmer. Humans have changed sufficiently that those terms are not accurate. Birds have changed sufficiently that “dinosaur” is not accurate. Sure, it’s neat to know that not all dinosaurs died out, that they kinda morphed into something else instead. But that’s not quite the same thing. > > I’m sure I’m going to get heaped on for that last one. 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. 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. Also, to clarify this: > [@](#): > > Their ancestry diverges from bony fish earlier in the timeline before bony fish. Sharks (Chondrichthyes) evolved from acanthodians, which had bones. Acanthodians also evolved into Osteichthyes, which are what are collectively and colloquially known as “bony fish”; that group is further subdivided into Actinopterygians (ray-finned fish, which includes most of the ‘traditional’ fish, such as carp, tuna, trout, marlin, guppies, etc.) and Sarcopterygians (“fleshy-finned” or “lobe-finned” fish), which includes coelocanths, and all tetrapods (including dolphins, killer whales, monkeys (including humans), and reptiles (including dinosaurs (including birds)), etc.). ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [March 28, 2015, 7:32pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/38 "2015-03-28T19:32:41Z")
> [@Irishman](#): > > To try to rephrase what **DrDeth** said… and do a much better job, thanks! 🙂 ---
**Author:** ![Really\_Not\_All\_That\_Bright](https://avatars.discourse-cdn.com/v4/letter/r/e8c25b/32.png) [@Really\_Not\_All\_That\_Bright](https://boards.straightdope.com/u/Really_Not_All_That_Bright)\ **Post date:** [March 28, 2015, 8:08pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/39 "2015-03-28T20:08:55Z")
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? ---
**Author:** ![Tamerlane](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tamerlane/32/7602_2.png) [@Tamerlane](https://boards.straightdope.com/u/Tamerlane)\ **Post date:** [March 28, 2015, 9:44pm UTC](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564/40 "2015-03-28T21:44:25Z")
> [@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? I decided long ago that they’re just big, opaque coelenterates and none of these fancy pants systematists can argue me different! [Previous page](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564.md?page=1) [Next page](https://boards.straightdope.com/t/killer-whales-are-a-type-of-dolphin/715564.md?page=3)