AP BIOLOGY

Detailed explanation-1: -A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group. This is especially important where the descendant group is sharply differentiated by gross anatomy and mode of living from the ancestral group.

Detailed explanation-2: -: a fossil that exhibits characteristics of both ancestral and derived forms. During the past 30 years, new discoveries and reinvestigations of long-forgotten specimens have coalesced into a flood of transitional fossils.

Detailed explanation-3: -Transitional fossils help scientists bridge gaps in the tree of life, resulting in a picture of gradual evolution over millions of years. Transitional Tetrapod Fossil: According to modern evolutionary theory, all populations of organisms are in transition.

Detailed explanation-4: -A transitional form is a living or fossilized organism that is believed to be an evolutionary link between two distinct groups (also referred to as intermediates or missing links).

Detailed explanation-5: -Romer’s Gap These gaps represent periods from which no relevant fossils have been found. Romer’s gap is named after paleontologist Alfred Romer, who first recognized it.