00:01
All right, so the question for today is asking which ones are the amniotes and which one is the exception, which one is not.
00:11
So i'm going to talk about two different groups of animals today.
00:14
The first one is the amniote.
00:21
And the second one is the tetrapod.
00:26
So there are two different groups of animals underneath the amniotes, which is one are the mammals.
00:37
And the other is reptile.
00:43
Now under tetrapods, you have amphibians.
00:50
So if you ever look at a phylogenetic tree, it starts with the ancestral cordata, which is just the spinal cord.
00:57
Of course, this follows the evolution of animals from fish all the up to amniotes and tetrapods, mammals.
01:04
And so, of course, with every evolution, there's a new characteristic that develops.
01:12
Now, with amniotes, tetrapods came first.
01:16
So it's those tetrapods and then amniotes.
01:20
So the key difference between amniotes and tetrapods are the amniotic egg.
01:28
Now, this egg is really important because it really helps with mammals and reptiles and the reproductive cycle of zygote into fetus into a baby.
01:40
Now, what helps this is what we call, happy face, amniotic fluid.
01:50
Now, i do want to give an example in terms of mammals where, of course, mothers are able to give birth to a baby.
01:57
The way this is done is the zygoturn turns into a fetus...