A. There were animals 3 billion years ago; they just weren't fossilized. B. Animals are warm-blooded; the ocean was too cold for animals.
Covalent bond? Carbon is usually the structure for a polymer Bc it can make up so many things including covalent bonds used to make polymers
Answer:
The hair shaft is comprised of three layers: the cuticle, cortex, and medulla.
Explanation:
A cladogram is a diagram of branches that show the cladistic relationship between animal species. A node you can expect to find on the cladogram would be <span>Deuterostome development. Examples of deuterostomes are starfish and sea cucumbers.</span>
I think that since it lives on the ocean floor, at the deepest of the ocean. So anyway, the fin on the Eurypterids is still necessary but not that much, since they live on the ocean floor. Their movements mostly on the ocean floor. So fin would not help them "stick" to the floor. Also there are still gravity acts on the Eurypterids and the feet would help them move faster. Hope this helps.
