Phylogeny + Anatomical Structures

Question 1

What are the three traits Phylogeny are based on?

Answer 1

Molecular, Structural and Developmental.

Question 2

What/How does the Phylogenetic tree work?

Answer 2

Groups of organisms based on the principles of phylogeny can be represented by a phylogenetic tree or cladogram. Whenever the branch divides, it shows the emergence of a new group of organisms.

It’s like the less menacing variant of a dichotomous key.

Question 3

What are some signs that Organisms likely share a common ancestry?

Answer 3

Same Embryonic stages (nearly), Similar Anatomical functions and they are generally similar.

All vertebrate embryos go through a stage in which they have gills similar to those of fish.

Question 4

Recap: Homologous Structures?

Answer 4

Similar Origin. Different Function. May only be seen in Embryonic stage.

Question 5

Recap: Analogous Structures?

Answer 5

Different Origin. Similar Function. Similar features evolve in different species to suit the surrounding environment.

Question 6

Recap: Vestigal Structures?

Answer 6

Practically Obsolete in the modern era.