Crinoids, also known as sea lilies, appear to be sea plants but are not plants at all. Crinoids are an echinoderm species which
uses anchoring structures called holdfasts to attach themselves to the sea floor. Crinoids were most abundant in Pennsylvania during the Mississippian Period, which ranged from 375 to 320 million years ago. Fossils of the crinoids shows that during most of this time Pennsylvania was ________ that provided favorable conditions for crinoid growth. A) glacial terrain B) a dry and sandy plain C) mostly mountain ranges D) covered by warm, shallow seas
The correct answer is - D) covered by warm shallow seas.
The fact that the crinoids are have an abundance in the fossil records in Pennsylvania in the Mississippian Period, tells us that this area was covered with shallow and warm seas. The reason why we can get that conclusion is that the crinoids live only in that kind of environment, so it simply a logical conclusion.
The geological data is also confirming this, as it is easily noticeable in the layers that during this period of the geologic past, what is now Pennsylvania, was covered with shallow sea waters. Also, this waters were warm too, as the climate was warm and humid and that period, so it was a perfect environment for the crinoids to flourish.
Any physical characteristic can be passed on from generation to generation. However, some characteristics are influenced by the environment as well as having a genetic predisposition for that specific trait.
Answer: First of all those are green boxes so i think u took a picture of the wrong slide or it was a typo. second of all, u didnt provide enough info for why and what words u are supposed to be placing blue boxes on in the first place. i guess its correct.
