Pandas are descendants of omnivores with a predator streak, them rat fucking their diet to near koala levels of bad doesn’t really factor in yet.
Comment on *confused flatfish noises*
squaresinger@lemmy.world 2 weeks agoPandas as well. Non-predator but clearly front facing eyes.
vaultdweller013@sh.itjust.works 2 weeks ago
Fedizen@lemmy.world 2 weeks ago
Idk if “descendants of omnivores” counts because then you could exclude a number of critters like pigs for being “descendants of herbivores” and then ‘why do pugs have forward facing eyes?’
The obvious caveat is that pandas at the minimum don’t have selective pressure for side eyes or they have something pressuring stereoscopic vision even more similar to how aquatic animals have less selective pressure for forward facing eyes.
vaultdweller013@sh.itjust.works 2 weeks ago
I was trying to imply that pandas did it recently enough for such pressures to not have kicked in yet. Probably should’ve specified that a bit better.
squaresinger@lemmy.world 2 weeks ago
Google tells me that pandas started eating bamboo 6-8 million years ago and stopped eating meat 3 million years ago.
That’s not exactly recent.
For reference, the first Homo appeared 2.8 million years ago and the first Homo Sapiens 300 000 years ago.
The last common ancestor of humans and chimpanzees lived 5-10 million years ago.
So if evolution can evolve humans in that time frame, you’d expect that it could also adapt an omnivour to a herbivour.
Fedizen@lemmy.world 2 weeks ago
That’s the speculation on gut length in pandas based on statistical methods but panda teeth are already well adapted to eat bamboo so selection has been working on them for some time or at least there is no opposing selection at work in panda teeth preventing them from changing. Strangly the large canines are used to cut the bamboo which might be what created their niche in the first place.
Its been a while since I dove into this but from what I remember the speculation with gut length has to do with metabolic tradeoff. If pandas don’t get that tradeoff with the food they eat then they’ll probably keep their current gut length.
DragonTypeWyvern@midwest.social 2 weeks ago
Or they need it that way to learn kung-fu
Auli@lemmy.ca 2 weeks ago
But Pandas are bears and haven’t changed much. They eat plants and their guts have not even evolved to do so yet. They are a wonder.
squaresinger@lemmy.world 2 weeks ago
They stopped eating meat 3 million years ago. That’s longer ago than the appearance of the first animal of the genus Homo.
Auli@lemmy.ca 2 weeks ago
Sure but their digestive system is still that of a carnivore.
pjwestin@lemmy.world 2 weeks ago
Yeah, but Pandas aren’t herbivores, they’re vegetarians. They’re too slow and clumsy to actually hunt prey, so the only thing they can catch is bamboo (which is the fastest growing plant, so I guess that’s something…sort of…). Anyway, the point is, Pandas as a species are from a family of predators, and they would absolutely eat meat if you gave it to them.
squaresinger@lemmy.world 2 weeks ago
Pandas stopped eating meat about 3 million years ago. That’s before the first being of the genus Homo appeared. Not Homo Sapiens (that was 300 000 years ago), but Homo Habilis (2.5mio years ago).
If evolution can take us from something that’s barely an ape to humans in that time frame, you’d expect that it can fix an omnivour’s digestive system to work with plants.
pjwestin@lemmy.world 2 weeks ago
My old biology teacher used to say, “evolution only works as well as it needs to.” Rabbits digestive systems are so inefficient they have to eat their own shit just to get enough nutrients. Hyena clitoris are so large they sometimes suffocate their offspring during birth. You’re mouth is full of vestigial molars that will likely require surgery in your lifetime. None of those things matter, as long as your genes are successfully being passed down effectively
Panda’s have a digestive system that’s not well suited to their diet, and they’ve adapted to that mostly through behavioral changes. Since they don’t have kind of stomachs that efficiently digest plant matter (like a cow’s four-chamber stomach), they’re constantly hunting for different types of bamboo to get the nutrients they need. They eat young bamboo shoots of one species in the spring, then migrate to higher elevations to get the shoots of another. Both shoots lack calcium, so they migrate again in late summer to get more mature plants calcium-rich leaves.
One weird physical adaptation they’ve developed is in their pregnancies. They mate in the springtime, but fetuses require lots of calcium to develop, so females embryos basically get, “paused,” neither developing or dying, until later in the season when they have more calcium in their diet.
Anyway, I guess my point is that evolution did fix the pandas digestive system to work with plants. It’s just that, like most of evolution’s fixes, it’s a solution that’s barely held together by duct tape and hope, and it could fall apart at any minute.
sbeak@sopuli.xyz 2 weeks ago
Is this because pandas used to be carnivorous? (they have sharp canine teeth despite pretty much only eating bamboo)
notsure@fedia.io 2 weeks ago
...i am withholding all judgments on pandas until my full research has been completed...i heard something on the internet...