Reptiles are more closely related to birds than amphibians so why? Idk why.
Because reptiles and birds belong to the same clade. See this ongoing topic: Are birds really reptiles?
In short, birds evolved from theropod dinosaurs during the Jurassic (~165 million years ago). Reptile and amphibian lines diverged in the Carboniferous (~325 million years ago). Mammal and reptile lines also diverged in the Carboniferous.
Edit: Sorry, I get thrown off when the question to be answered is only in the title but not in the text body. I thought you were asking why reptiles are more closely related to birds than amphibians.
Because herpetology dates back to pre-Darwinian times when phylogenetic relationships were not well understood. It made sense to lump together the cold-blooded tetrapods and to distinguish them from other vertebrate groups which had their own -ologies.
Also some of the same field techniques are used in the study of reptiles and amphibians so theyâve been kind of grouped together as a discipline for a long time. Research museums generally keep their amphibian and reptile specimens together, in a herpetology collection, since preservation and storage methods are very similar, which further links the two. Some of this is historical inertia, some is practicality.
They are herps because the term comes from the Ancient Greek meaning crawling, an apt description for most and not applicable to birds.
Itâs fun to consider that when Linnaeus first applied his nomenclatural scheme to the natural world, he came up with four types of herptiles: shelled things (turtles/tortoises), 4-legged things with tails (salamanders, lizards, crocodiles), 4-legged thing lacking tails (frogs/toads), and legless things (snakes, legless lizards) using just four modern taxon namesâŚTestudo, Rana, Lacerta, Anguis. There were other genera and species listed within these, but in Linnaeusâ mind those four types we good enough to capture the variation of crawling things.
Everything was so much simpler in the old days, says the old retired guy (me).
All you needed was a bible. You had your âbeasts,â your âcreeping things,â your âfowls that flyâ and the âthings that swim.â There were also plants with seeds and fruits.
And Iâm over here calling inverts herpsâŚ
Because visual categories can be as meaningful as hypothetical lineages, and for some use cases, more so.
What does that mean?
The solution is a good one, but I believe the grouping has also stuck because people want to quickly describe ânon-fluffy thingsâ.
Learning about evolution has finally vindicated my love for lizards, snakes, and birds, yet not caring so much for amphibians : )