So by looking at the seismic waves from earthquakes the scientist learned about the crust and the mantle but they also learned about the outer and inner core. To do this you have to look at a different kind of waves, the S (secondary waves) waves that also get released by an earthquake.
D) The AV valves are supported by chordae tendineae so that they do not blow back up into the atria during ventricular contraction.
Cause mammals are the only species that are well developed before birth unlike marsupial and monotremes
The correct answer of the given question above would be the third option: THE EVOLUTION OF POPULATIONS OVER TIME. What is represented by the base of a phylogenic tree is the evolution of populations over time. It is also known as the evolutionary tree. This tree shows the evolutionary relationships among species.
<span>i think Comparative morphology
i could be wrong tho</span>
