Answer:
Rat. The laboratory rat, Rattus norvegicus, belongs to the order Rodentia and family Muridae. Rats were first used for experimental purposes in the mid 1800s. Strains were developed to study neuroanatomy, nutrition, endocrinology, genetics and behavior.
Explanation:
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I believe it's Lower.
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Answer:
Pioneer species move into an area after a disturbance that forms new land without soil. Pioneer species are the first organisms to colonize an area that has undergone primary succession
Explanation:
They do this so more species can thrive in an area