Even
though sarcopterygians
are
fishes, they are the common ancestor of all the tetrapodes (we humans
included). Sarcopterygians
have
lobe-fins which
are muscular fins with a single bone that articulates with the rest
of the body. Lobe-fins are basically limb precursors. In fact, every
vertebrate have lobe-limbs that originated from the lobe-fins of the
sarcopterygians,
so
in a very real sense er and all the vertebrates alive are descendants
of the sarcopterygians
fishes
that lived in the Devonian 419.2 million years ago.
