Afamily has two male children one brother has a straight thumb a straight thumb while the other brother has a bent thumb what causes this difference

Which of the following statements is true? a. the main cause for speciation is an increase in gene flow. b. organisms that reproduce asexually are not considered part of a species. c. on a tree of life diagram, speciation is shown by the merging of two different lineages. d.the size of the geographic area inhabited by a population can cause speciation.

State officials are considering constructing a road through a forested wilderness area. this action will likely affect the forest ecosystem in various ways. part a: predict how the construction of a road could negatively affect plants and animals in that ecosystem. (3 points) part b: describe one way that the construction of a road could have a positive impact of the forest ecosystem. (1 point)

In many humans, exposing the skin to sunlight over prolonged periods of time results in the production of more pigment by the skin cells (tanning). this change in skin color provides evidence that -