Ask Dr. Galapagos Steve: Are dolphins considered whales? Dear Steve, I wrote you and told you that dolphins are indeed (never trust people who use the word indeed) whales, and that is still my opinion. But not everyone agrees with me so here is a little more explanation. If you look around the web or look in a lot of other sources for information on whales (like books - books are still the best place for information - go there often) you will find, as I did, that some people say dolphins are whales and some people seem to say dolphins are not whales. It is common for even scientists to separate these marine mammals into whales, porpoises, and dolphins (in fact this seems to be the norm). And sometimes the same people who say that dolphins and porpoises are not whales will turn right around and tell you that dolphins are members of the "toothed whale" club. (Club is not an official science word, so more correctly, the suborder "Odontoceti".) Apparently they are "toothed whales" but not whales!? And so the confusion starts. What's going on? The problem is us! We have met the problem and it is us. We laypersons tend to not be too careful with our words. When most of us say whales we mean something kind of vague but generally a lot bigger than a dolphin. And when we say dolphin, we mean the little smiling guys that put on shows for us at places like Marine World. <3dlphns.jpg> But what about killer whales? They are supposedly in the same suborder as dolphins (and even in the same family - Delphinidae) but they have whale in their name. The same is true of pilot whales and narwhals (note that whal is not whale) and beaked whales and bottlenose whales. <3nrwhals.jpg> Since general words like whale and dolphins can be unclear, taxonomists use another word. The word they use is cetacean (pronounced as seet-asian). All whales, dolphins, and porpoises are cetaceans. No one is allowed to argue about this (in theory - in reality there is always discussion and things are always changing). So chill out! The next time someone starts to argue about whether or not a dolphin is a whale just roll your eyes, smile smugly, and say, "I don't get bogged down in such silly arguments. To a marine biologist they are all cetaceans". (And, of course, you can also tell them that Dr. Galapagos says a dolphin is a whale is a cetacean. That should settle it.) Teeth or Baleen? Here is how the taxonomists tell us to classify whales, er, I mean cetaceans. First there is the Kingdom. They are in the animal kingdom, or Animalia, to be all "Latiny" about it. Next there is a Phylum. Cetaceans are in the Chordata phylum, which means they are vertebrates (they've got backbone). Of course, they've got Class, lots of class. They are in the Mammalia class. That's us too! We humans are mammals too. Just like the whales! Next comes Order. Their order is Cetacea. Proud members of the Order of the Cetacea. Sometimes there are Suborders, too. There are two suborders, toothed whales and baleen whales, in the Cetacean order. We'll define them in another article. The scientist name for toothed whales is Odontoceti. The scientist name for baleen whales is Mysticeti. (Because they are so mysterious?) Baleen whales include blue whales (really really big), fin whales, right whales (there are no wrong whales), gray whales, humpbacks and others. After suborder comes Family. Killer whales and dolphins are in the Dolphinidae family. By our count there are 11 cetacean families. After Family comes Genus. Check out the table below to see some examples of genus and species names. Finally, we get to the specific Species. A good source tells us there are 79 known species of cetaceans. The further down the list you go the more alike the animals get. Animals of the same species are so much alike they can reproduce and their offspring can reproduce more of the same. Below is a table showing how whale biologists (oops, I mean, Cetacean biologists) have classified some of the better known cetaceans. Bottle Nose Dolphin Killer Whale Blue Whale Humans Tursiops truncatus Orcinus orca Balaenoptera musculus Homo sapiens Kingdom Animalia Animalia Animalia Animalia Phylum Chordata Chordata Chordata Chordata Class Mammalia Mammalia Mammalia Mammalia Order Cetacea Cetacea Cetacea Primates Suborder Odontoceti Odontoceti Mysticeti Family Delphinidae Delphinidae Balaenopteridae Hominidae Genus Tursiops Orcinus Balaenoptera Homo Species truncatus orca musculus sapiens The Order Odontoceti Dolphins belong to the suborder Odontoceti, which means they are "toothed whales". Other toothed whales include sperm whales (the biggest), beaked whales, bottlenose whales, porpoises, beluga whales, narwhals, river dolphins, pygmy sperm whales, and dwarf sperm whales. The Family Delphinidae Killer whales are in the same family as dolphins. The big name that taxonomists use for this family is Delphinidae. Members of the delphinidae family are ocean going dolphins (as opposed to river dolphins). So killer whales are in the same family as dolphins. Does that mean they are not whales? Should we call them Killer Dolphins? Does it matter? Killer whale chasing a seal Inside the mouth of the orca (a kinder gentler name for killer whale), is the last thing that some seals, sea lions, fish, squid, porpoise, whales, and many other sea creatures ever see. Orcas are friendly to each other, and pretty friendly to us humans, but they will eat just about everybody else. The Family Monodontidae The strange looking Narwhals are also members of the toothed whale (odontoceti) club. But they are not in the dolphin family. They are in the Monodontidae family. The other lonely member of this family is the Beluga whale. Monodontidae are white whales with blunt heads and no dorsal fin. That big spike coming out the whale's forehead is really its left upper tooth. Only males have this "tusk" and no one is quite sure what it is used for. Narwhals live in the arctic and are said to be rare. The Class Mammalia Seals are not cetaceans. They are pinnipeds. Seals, sea lions, and walruses are pinnipeds. Pinnipeds and cetaceans are both considered marine mammals. Sealions Walrus Sea lions are cute. Sea lions are more flexible than seals, and get around on land a lot better (which isn't saying much). Killer whales will enthusiastically eat either seals or sea lions (and many other marine creatures too). They are non-biased eaters. BOX Will the Correct Taxonomist Please Stand Up? There are scientists called taxonomists (no, they didn't invent taxes) who have taken it upon themselves to classify all living things into kingdoms, phylums, classes, orders (and sometimes suborders), families, genuses, and last but not quite last, species (there are also subspecies sometimes). These people argue amongst themselves and lose sleep at night worrying whether or not dolphins are whales. Well, actually, what they really worry about is the confusion that is caused by ordinary people like you and I using such unclear words as dolphin and whale. It is important to whale biologists when they talk or write to each other that they be very clear so that there are no misunderstandings. Or at least as few misunderstandings as possible. So what do whale taxonomists do? They decide which whales are related to which other whales and organize them all into families and orders and genuses and species. Then they make up very precise names (with the help of an old language like Latin) and define as precisely as possible what that name applies to. Then everybody knows just what they are talking about. Even people who speak different languages know. Whether they speak Russian or Spanish or Swahili, they all know that a Balaenoptera Musculs is a blue whale and a Tursiops Truncatus is a bottlenose dolphin. I poke a little fun at taxonimists here, but it is really a fascinating and fast changing field. It's changing because we are learning more, each day it seems, about the genetic code of more and more species and discovering there are some surprising possible new relationships amongst the various species. And, of course, we laymen need them to settle questions of nomenclature. Nomenclature is all about what things should be called. (Taxonomy is all about deciding how to organize and group living things logically and who is related to whom.) Because words like Dolphin and Whale are often not clearly and officially defined, we need the taxonomists to give us words like cetacean and delphinidae, that are clearly defined. The great gods of Taxonomy (that is, the taxonomists) decide who is an official cetacean and who isn't. Nobody is officially regulating inexact words like whale and dolphin. This means we laypersons are free to be as confused as we like, and to argue all we want, about them. It gives us something to do. From The Flying Turtle Web-site: http://www.ftexploring.com/ (Dr. Galapagos answers other equally fascinating questions on this web-site.)