> Wait a second... What are bats and rabbits doing on today's Reader Poll? They're not exactly rodents, last time I checked...
>
> -- codeman"ok, so I'm a nitpicker"38

Wow. I'm wholly delighted with Sam's Poll Question today, because it gave me a chance to go back and review the genetic databases available at GenBank. Things have changed so much thanks to biomolecular sequence classifications! Before, we had to rely on relatively crude, error-prone, and terribly subjective anatomical comparisons between species; nowadays, automated DNA footprinting by computer permits an objective and dispassionate method of finding the relationships between species.

Consider Mammals. Under the Mammalian CLASS Theria, there are two Infraclasses: Marsupials and Placentals. All the small, furry creatures on Sam's list are related by being Placentals (rather than by being Rodents). Humans are Placentals too, of course.

Sequencing shows that bats, ferrets, rabbits, racoons, and weasels are not Rodentia, unfortunately. :)

A selected Taxonomy lineage of those creatures is as follows:


INFRACLASS Metatheria (Marsupials): (the Koala, Bandicoots, Opossum, Wallabies, Wombats)

INFRACLASS Eutheria (Placentals):

/ / / / ORDER CARNIVORA:
/ / / / / / / / Family Mustelidae: (Ferret, Weasels, Badgers, Skunks, Otters, Minks, Ermines, Wolverine)
/ / / / / / / / Family Procyonidae: (Racoons, Coatimundi, Kinkajou, Lesser Panda)
/ / / / / / / / Family Viverridae: Civets

/ / / / ORDER CHIROPTERA: Bats
/ / / / ORDER EDENTATA: (Armadillo, Sloths, Mexican Anteater)
/ / / / ORDER INSECTIVORA: (Shrews, Moles, Hedgehogs, Tenrecs)
/ / / / ORDER LAGOMORPHA: (Rabbits, Hares, and Pikas)


/ / / / ORDER RODENTIA:

/ / / / / / / / Suborder Hystricognathi
/ / / / / / / / / / / / Family Caviidae: Guinea pigs
/ / / / / / / / / / / / Family Chinchillidae: Chinchilla
/ / / / / / / / / / / / Family Erethizontidae: New World Porcupines
/ / / / / / / / / / / / Family Hystricidae: Old World Porcupines

/ / / / / / / / Suborder Sciurognathi
/ / / / / / / / / / / / Family Castoridae: the Beaver
/ / / / / / / / / / / / Family Geomyidae: Pocket Gopher
/ / / / / / / / / / / / Family Muridae: (Mice, Rats, Gerbils, Hamsters, Lemmings, Muskrats, Voles)
/ / / / / / / / / / / / Family Sciuridae
/ / / / / / / / / / / / / / / / Subfamily Petauristinae: Flying Squirrel
/ / / / / / / / / / / / / / / / Subfamily Sciurinae: (Squirrels, Chipmunks, Woodchuck/groundhogs/marmots, Prairie dogs)


Taxonomy: So Woodchucks/Groundhogs/Marmots are classified as giant squirrels, basically. :) It's interesting how things turn out. I wouldn't have thought offhand that Raccoons and the Lesser Panda are related genetically, but it makes sense in hindsight -- think of their eye-patches. And I can see how Ferrets and Skunks might be related, but to find that Skunks are also related to Sea Otters?! It's beyond all imagination and wonder.

Wolfspirit