Over evolutionary time, many cave-dwelling organisms have lost their eyes. Tapeworms have lost their digestive systems. Whales have lost their hind limbs. How can natural selection account for these losses?
A) Natural selection cannot account for losses, only for innovations.
B) Natural selection accounts for these losses by the principle of use and disuse.
C) Under particular circumstances that persisted for long periods, each of these structures presented greater costs than benefits.
D) The ancestors of these organisms experienced harmful mutations that forced them to find new habitats that these species had not previously used.
Evolutionary shift in plant life cycle stage dominance.
Evolutionary tree derived from amino acid sequence comparisons
Time Line of Human History From Upper Paleolithic Period to the Present
Microbes that have become model organisms for genetic studies
A very small sampling of organisms in an arctic food web on land.
Incomplete dominance in flowering time of pea plants