A group of scientists wanted to investigate how populations of organisms can change over time. They decided to study a population of birds on the Galapagos Islands exposed to extreme conditions of drought. Which of the following would be the best hypothesis to test how the birds might adapt to these conditions over time?
A. Birds exposed to extreme drought will become less attractive over time.
B. Extreme drought conditions could cause bird species to become extinct.
C. If birds are exposed to extreme drought then their beak size will quickly change overnight.
D. Birds might breed with other species and adapt to these conditions.

The diagram shows a fossil of an ancient whale skull and a skull of a present-day whale. the ancient whale is extinct and is believed to be an ancestor of the present-day whale. what do these skulls most likely show that supports darwin’s theory of evolution? all populations can adapt and survive. only some organisms have a common ancestor. populations change slowly over time. populations rapidly become extinct.

Over the past 60 years, many amphibian species have experienced significant population declines and some species have become extinct. scientists suspected that local human activities such as the destruction of wetlands, regional pollution, and deforestation were the main reasons for these losses. however, research over the past 20 years reveals significant amphibian population declines in protected areas of the world, such as nature preserves and parks. these global declines suggest widespread problems including increased ultraviolet radiation, acid rain, and disease. in switzerland, for example, 14 of the 20 native amphibian species are threatened with extinction. chytridiomycosis is a fungal disease first identified in 1998 as a cause of massive amphibian deaths. in some severely impacted populations, a few individuals have survived, perhaps because of some natural resistance. if these resistant individuals continue to survive and prosper, new resistant populations might emerge. this would be an example of the founder effect artificial selection genetic drift natural selection sexual selection

This is the amino acid cysteine. circle the amine group, put a box aroundthe carboxylic acid group and use a different colored pencil/pen to circle the sidechain (r group). h o | ||nh2— c- c-oh | ch2 | sh