Ecological fitting can contribute to 3 types of evolutionary transition.

This evolutionary transition appears to have left its mark on tetrapod development.

The evolution of networks of cooperating genes ultimately led to the enclosure of separate hypercycles within protective membranes to form proto-cells, the second major evolutionary transition.

In fact, as much as 90% of the genetic material can be lost when a species makes the evolutionary transition from a free-living to obligate intracellular lifestyle.

Trees are scored (evaluated) by using a simple algorithm to determine how many steps (evolutionary transitions) are required to explain the distribution of each character.