1) Hunting: People can over-hunt a species killing too many of them too fast.
2) Global warming: A place can get to hot for them to survive their anymore like coral reefs for example.
3) Destruction of habitats: This can leave animals defenseless and open to attack.
Answer:
potassium-argon dating
Explanation:
Potassium-argon (K-Ar) dating technique is the most appropriate dating method for establishing the age of a volcanic ash. It is most applicable for dating minerals and rocks more than 100,000 years old. It is based on measuring the product of the radioactive decay of an isotope of potassium (k) into argon (Ar). Since potassium is a common element found in many volcanic ash layer, the time since re-crystallization is calculated by measuring the ratio of the amount of argon 40 (Ar-40) accumulated to the amount of potassium 40 (K-40) remaining in these volcanic ashes.
Answer: migrantes estão no caminho e não se sabe do estatus deles {exilados, fugitivos etc etc} e nem sempre sabemos o objetivo, ponto final ou destino deles. Imigrantes são pessoas que acabaram de chegar no país que lhes recebeu (expressao "imigrantes" descreve a perspectiva dos habitantes do pais que lhes recebeu). Emigrantes sao aqueles que abandonam o país (expressao "emigrantes" descreve a perspectiva do habitantes do país de origem).
Explanation: As três palavras tem significado diferente e sempre requerem compreensao. Migrante está no caminho, imigrantes está chegando ou já chegou, emigrante está abandonando o pais de origem.
Ocean wind circulation mainly mechanism climate change Earth