Which of the following scenarios represents change to an ecosystem brought about by biotic factors? a. a wildfire caused by lightning striking a tree b. a flood caused by a severe storm c. a landslide caused by cattle overgrazing d. a volcano

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".

protein makes up the building blocks of organs, muscles, skin, hormones and pretty much everything that matters in your body.

some choices are:

peanut butter

seeds

eggs

yogurt

meats

fish

so pretty much meat, dairy, nuts, and grains.