The least effective kind of light bulb is the

The image shows embryos of three vertebrate classes

How does the molecular clock work? a. it analyzes the brain functionality of two different species. b. it examines and compares the physical characteristics of two different species. c. it illustrates relationships between two different species. d. it compares the number of mutations that exist in the dna of two different species.

Why do oceanic plates tend to subduction when colliding with a continental plate