In early america what dangerous geographic barrier caused problems during the great eurpoean migration?

Which of the following is defined as combinations of soil particles that vary in size and shape?

Which anatomical feature would you expect to find in the fossil remains of a nocturnal species?

The declining axolotl population in mexico city is an example of in overcrowded cities. a. the surpassing of support capacity b. changes to natural environments and native species c. the lack of safe homes and tenured spaces d. the effects of a growing urban heat island