what happened to the natives living there?
They became the victims of starvation and disease.
California Gold Rush
The human and environmental costs of the Gold Rush were substantial. Native Americans, dependent on traditional hunting, gathering and agriculture, became the victims of starvation and disease, as gravel, silt and toxic chemicals from prospecting operations killed fish and destroyed habitats. 
crustacea and hexapoda have what features in common It is now well accepted that the crustacean group is paraphyletic, and comprises all animals in the clade Pancrustacea other than hexapods. what is the first group that you are talking about? It forms a large, diverse arthropod taxon which includes such animals as crabs, lobsters, crayfish, shrimps, prawns, krill, woodlice, and barnacles. can you describe their body? It is composed of segments, which are grouped into three regions: the "cephalon" or head, the "pereon" or thorax, and the "pleon" or abdomen. and where do they generally live? Majority live in either marine or freshwater environments. have their fossils been found? Yes, they have a rich and extensive fossil record. can you name any organism of this taxon whose fossil has been discovered? Yes, "Canadaspis" and "Perspicaris". how is the former classified? It is currently thought to be a member of the group Hymenocarina. which members of the original taxon that we were talking about are consumed by humans? Crabs, lobsters, shrimp, crawfish, and prawns. what is the third one? They are decapod crustaceans with elongated bodies. where are they found? Most shrimp species are marine, although about a quarter of the described species are found in fresh water. can you mention any evidence of consumption of this creature during ancient times? In the mid nineteenth century, Chinese immigrants arrived for the California Gold Rush, many from the Pearl River Delta where netting small shrimp had been a tradition for centuries. can you tell me a little bit more about the rush? It was found by James W. Marshall. what is it about? The news of gold brought approximately 300,000 people to California from the rest of the United States and abroad.
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California Gold Rush [SEP] Impact on Native Americans
The human and environmental costs of the Gold Rush were substantial. Native Americans, dependent on traditional hunting, gathering and agriculture, became the victims of starvation and disease, as gravel, silt and toxic chemicals from prospecting operations killed fish and destroyed habitats. The surge in the mining population also resulted in the disappearance of game and food gathering locales as gold camps and other settlements were built amidst them. Later farming spread to supply the settlers' camps, taking more land away from the Native Americans. In some areas, systematic attacks against tribespeople in or near mining districts occurred. Various conflicts were fought between natives and settlers.