Crabgrass, also known as digitaria sanguinalis, is a stationary multicellular species that belongs to kingdom Plantae. According to the table below which of the following species is most closely related to digitaria sanguinalis?

Asquirrel population lives in an area. over many years, a river in that area grows wider and stronger, eventually forming a canyon. the squirrel populations on the two sides of the canyon can no longer mate with each other and ultimately form distinct species. this is an example of

How does the color of light affect the germination time (amount time a plant takes to develop) of a radish seed?

Which of the following must be true for a fossil organism to be useful as an index fossil? a. the fossil organism must be widespread geographically. b. the fossil organism must be abundant. c. the fossil organism must be limited to a short span of geologic time. d. all of the above.