People in northern climates are familiar with flocks of birds flying south in the winter, but why do they do it, and why don't they just stay where it's warm?

When the lights change, the birds hop in front of the cars and place walnuts, which they picked from the adjoining trees, on the road. After the lights turn green again, the birds fly away and ...

an introduced parasitic fly whose larvae feed on the finch's nestlings. Causing high nestling mortality, lower fledgling success, and reduced nestling growth, the parasite appears to be hitting the ...

They make their homes in in woodpecker holes, nests abandoned by birds, or tree cavities in forests, woodlands, and jungles. Aside from their patagia, flying squirrels look similar to their ...