The proterozoic era is defined by the following events: eukaryotic cells first seen stable continents first bacteria fossils the cambrian explosion oxygen building up in atmosphere

The asian shore crab (hemigrapsus sanguineus) is an invasive species that has impacted the atlantic coast. predict what characteristic of this invader would most likely disrupt the biodiversity of this area.

Consider darwin's first writings on the theory of natural selection. an important point of darwin's essay on the principle of population, written in 1798, was a peer's observation that in nature plants and animals produce far more offspring than can survive, this observation can be attributed to a) charles lyell. b) thomas malthus. c) jean-baptiste lamarck. d) johann friedrich meckel.

Long-period comets come from the oort cloud particles in earth’s atmosphere material from the asteroid belt the kuiper belt