C. Permafrost
Permafrost is the layer beneath the "active layer". The active layer consists of soil that freezes and thaws every year. However, the requirement for permafrost is that it be frozen for two or more years consecutively. This is why permafrost exists in cold environments such as tundras.
It would decrease as their prime food source would be taken away. This would result in a decline in population as the birds wouldn’t have sufficient food.
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True because they grow the same may..Their cell mature the same way
Answer: Carbon 12 and Carbon 13
In plant, the ratio of carbon 12 and carbon 13 isotopes is different depending upon the plant photosynthesis. The distribution of these isotopes in plant tissue can indicate the path way of carbon metabolism that is either C3 fixation or C4 fixation. This help scientist to know if the plant consumed by organism is C3 plant or C4 plant by measuring the isotopic signature of their collagen and other tissues.
This can help scientist know which plant is consumed by animals.