Answer:
Bridgham et al. (2006) showed that the interaction between a steroid hormone (aldosterone-M) and its receptor (mineralocorticoid) evolved by Darwinian gradualism. In this work, the authors demonstrated a primitive affinity between the hormone and its receptor that was initially present in chemically similar but more ancient ligands. This result has implications in understanding the association between gene duplication and the evolution of hormone signaling pathways. For example, in invertebrates, this work reinforces the importance of gene duplication in the existing interaction between paralogous glucocorticoid receptors and their receptor mineralocorticoid genes that were derived from duplication (Thornton 2001).
The publications above cited are the following:
J.T. Bridgham, S.M. Carroll, and J.W. Thornton (2006). Evolution of hormone-receptor complexity by molecular exploitation. Science, 312(5770), 97-101.
JW Thornton. Evolution of vertebrate steroid receptors from an ancestral estrogen receptor by ligand exploitation and serial genome expansions, Proc Natl Acad Sci USA (PNAS), 2001, vol. 98 10 (pg. 5671-5676).
C Fossils allow scientists to have an idea of the time scale that traits evolved.
Correct Answer: D Shingles
this question was asked a week ago so you probably have moved or found an answer.. but nonetheless!
Shingles is a <u>viral infection</u> caused by the varicella-zoster virus (the same virus that causes chickenpox).
All the other disorders are caused by a bacteria.
The cause of the change in insect characteristics occurred when a few survivors of the 1st spray became resistant to the insecticide. When they had offspring, those insect babies are born with the trait that made them resistant to insecticide. This occurs when the parents pass on the trait to their offspring. The end result is that the insecticide is less effective and more insects survive.
Answer:
Energy Pyramid Definition. An energy pyramid (sometimes called a trophic pyramid or an ecological pyramid) is a graphical representation, showing the flow of energy at each trophic level
Explanation: