I wish people would stop putting turtles in the tortoise tag and tortoises in the turtles tag. They are NOT EVEN IN THE SAME TAXONOMIC FAMILY GUYS.
YES they look ~sort of~ alike. But let me break it down for you.
Everybody remember King Phillip Came Over For Good Spagetti? Kingdom Phylum Class Family Order Genus Species?
Each grouping is a great big circle. So, in the ANIMAL KINGDOM, you get all the vertibrate and invertibrate life on the planet. That’s a lot. Turtles and tortoises and crocodiles and snakes and spiders and people and birds all fall into this kingdom (you’re saying Duh to me. shhh.)
Ok, next step (the next smallest circle) for this is PHYLUM. In the PHYLUM CORDATA you get chordates. That’s basically anything with a nerve chord. In most cases this means vertebrate life, but it also includes some fun invertebrates. So, fish, turtles, birds, people, snakes, lizards, dogs etc.
NEXT step is CLASS. Traditionally the turtles and tortoises have been placed in CLASS REPTILIA, but this is soon to change to their own CLASS CHELONIA because although they share some characteristics with reptiles, they are not in fact closely related to them (fun fact, the crocodilians are getting their own class too)
Still with me? I know this is tough.
You get the idea, we’re basically separating LIKE from NOT LIKE.
Turtles and tortoises part ways at the level of ORDER.
I’m serious. THEY ARE NOT EVEN IN THE SAME FAMILY.
What does that mean? To use a mammal comparison, all mammals are in CLASS MAMMALIA, just like all turtles and tortoises are in CLASS CHELONIA (or Reptilia by the old system). At the level of Order for mammals, you have Order Carnivora (which includes bears, cats, and weasels) and 18 other orders such as Order Primates (which includes monkeys, lemurs, apes, and HUMAN BEINGS).
TLDR: Humans are more closely related to apes and lemurs taxonomically than tortoises are to turtles.
I commend you for this post. Its important information for lovers of all chelonians. I hesitate to say anything other than that because not only are you obviously right but you actually explain the difference better than most resources I’ve found available to the pet owner or non academic info seeker. So thanks!!
To defend myself (and others I know), when wanting to share some fantastic pictures, info, news, etc with as many people as possible, using both terms as tags gets a larger readership with potential interest in both turtles, tortoises, or either. Doing that you find people with a willingness to look at posts related to either and get a chance to share stuff like this with everyone 🙂
Lastly I’d like to say, Herpetology FTW!