Which of the following could be considered the most recent common ancestor of living tetrapods?
A) a sturdy-finned, shallow-water lobe-fin whose appendages had skeletal supports similar to those of terrestrial vertebrates
B) an armored, jawed placoderm with two pairs of appendages
C) an early ray-finned fish that developed bony skeletal supports in its paired fins
D) a salamander that had legs supported by a bony skeleton but moved with the side-to-side bending typical of fishes
E) an early terrestrial caecilian whose legless condition had evolved secondarily
The Common Pochard, Aythya ferina, is a medium-sized diving duck.
Symptoms that are most common in toxic spider bites
Common sites of colorectal cancer.
Prolapsed uterus. (a) A prolapse is the abnormal drop of the uterus into the vagina, representing th
Photos simulating vision with two common visual disorders
Incidence of the Ten Most Common Cancers