Question

a critter has eight webbed feet, porous bones, and a green body has been discovered. what two places would you possibly think to put this? would it even be in the clade? why or why not?

Answer 1

ANSWER :-

1. Presence of webbed feet is a character which is seen in aquatic birds and amphibians like frogs. So, it can belong to the class Amphibia or Reptilia. Presence of eight legs do not specifically mould them in the phylum Arthropoda.

2. Porous bones are characteristic features of birds which helps them in flight. They lower the body weight and thus the bone density decreases as bone marrow is highly reduced. So, this can help to identify the animal to belong to class Aves.

3. Green body does not seem to be clearly a well defining character specific to a class or phylum although frogs do show presence of green and slimy surface.

4. So, the target critter has eight legs which are webbed and have porous bones. These two characters can group the organism either into class Aves or as a descendant of both the class Aves and Reptilia.

5. Monophyletic groups can be considered in terms of cladistic analysis as having a single common ancestor. Aves belong to a single monophyletic group composed of the reptiles. In this terms, they can be considered as a part of clade.

6. In case of class Amphibia and class Aves, it may be regarded to be a result of convergent evolution showing presence of webbed feets in comparison with the porous bone of the birds. But, this is just a possibility and not a conclusion unless genetic and molecular data is available.