Researchers looking for fossils of the earliest life forms face many hurdles. For example, few sedimentary rocks date back more than 3 billion years. Review what you learned about plate tectonics (Section 16.5). Explain why so few remaining samples of these early rocks remain.

Charles darwin published his theory of evolution in 1859. in what way foes modern evolutionary theory differ from the theory as proposed by darwin? a) darwin inferred that individuals can evolve, but modern generic science has shown that this is not true. b)darwin inferred that individuals do not evolve, but modern genetic science has shown that this is not true. c)modern science has disproved most of darwin's original theory of evolution, because darwin knew nothing about generations and their role in heredity. d)generic studies have shown that gene expression and other factors operate along with natural selection, but most of darwin's theory has been supported by modern science.

What sentence best supports the statement that hormones are involved in the regulation of homeostasis? a. the hormone erythropoeitin increases the production of red blood cells when oxygen levels are low. b. the hormone oxytocin promotes labor contractions of the uterus during childbirth. c. the hormone melatonin induces sleep and its production is slowed by exposure to light. d. the hormone cortisol suppresses the immune system and is produced when the body is under stress.

Migration is a. the movement of organisms from a native location to a foreign location b. the movement of organisms from a foreign location to a native location the movement of organisms from their water supply to their food supply d. the seasonal movement of organisms between locations c. select the best answer from above