Me fast , you (: scientists find evidence that the genes involved in tooth development exist in chickens, even though chickens do not normally develop teeth. the formation of teeth in chickens can be controlled by introducing a virus into chicken embryos that "turned on" their tooth-developing gene. they find that the beaks of the virus-modified chicken embryos contain cone-shaped teeth similar to embryonic crocodile teeth. which of the following best describes the conclusion that can be drawn from this experiment? a as bird evolution continues, birds like chickens will develop teeth like dinosaurs and reptiles. b the growth of teeth in chickens supports the hypothesis of a common ancestor between birds and reptiles. c the chickens with teeth are more closely related to crocodiles than they are to regular toothless chickens. d with enough genetic engineering, chicken embryos can develop into reptiles like crocodiles.

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

The organelle pictured is found in cells of and is theorized to have once been an independent organism.

Which is the correct order in the scientific process? ask a question ® form a hypothesis ® make an observation ask a question ® make an observation ® form a hypothesis make an observation ® form a hypothesis ® ask a question make an observation ® ask a question ® form a hypothesis