Key examples of index fossils include several species of , which are an extinct group of marine animals whose hard-shelled bodies had three sections.

Need will mark ! which features are created by groundwater erosion and deposition? check all that apply. a. stalagmitesb. sinkholesc. rillsd. stalactites e. gullies f. rivers

Next pretest: evolution select the correct answer in a laboratory population of flies, the female flies are gray and the males are yellowish gray. biologists observed that all the male flies had an equal chance for reproduction, but the male flies with the brightest colors were more likely to successfully reproduce. what phenomenon could explain such a change? a sexual selection b. disruptive selection c. stabilizing selection d. directional selection

What is a codon and where is it found