Winter squash is an excellent source of vitamin A, vitamin C, alpha-carotene and beta-carotene. It is also a very good source of thiamin, vitamin B6, potassium, magnesium, and manganese, and a good source of iron.
Spiders are, for the most part, such generalist feeders that they kill many useful insects as well as many pest species, however because pest species are by their nature more numerous than beneficial species they are still effective. They are of great value to the environment.
What was the contribution of Charles Darwin in the field of biology? Charles Darwin's contribution to the field of biology was the theory of evolution due to natural selection. This attempts to explain how species adapt to their environment â¦ s, sometimes leading to the development of new species.