恆溫與變溫動物?

Birds are homoiotherms, but the reason why they migrate is in this paragraph.

Many bird species migrate to 1. take advantage of global differences of seasonal temperatures , therefore optimising availability of 2. food sources and 3. breeding habitat .

恆溫, 去溫暖的地方唔代表佢地怕凍, 可能係for food, 而且變溫動物大多係冬眠, 並唔係migrate

恆溫動物,因BIRD己是恆溫動物,就是這樣EASY