Choanoflagellate adhesion proteins are similar to those of animals, and researchers have discovered that even solitary choanoflagellates have these proteins. What is the current hypothesis about the relation between the choanoflagellate adhesion proteins and animal adhesion proteins?

Question

What will be an ideal response?

Answer 1

By one hypothesis, the common ancestor of animals and choanoflagellates was a single-celled protist with adhesion proteins that helped it capture prey. Later, these proteins were put to use in a new context, helping choanoflagellates stick together to form multicelled colonies. Later still, the proteins allowed animal cells to adhere to one another in multicelled bodies. This modification in the use of adhesion proteins is an example of exaptation, an evolutionary process by which a trait that evolves with one function later takes on a different function.