Scientists estimate that the composition of Earth’s atmosphere has changed over time. Which of the following most likely caused Earth’s atmosphere to support diverse life-forms?
A: the drift of continents
B: a transfer of gases from the Sun
C: changes in Earth’s magnetic field
D: oxygen-producing organisms

Which of the following scenarios is an example of the bottleneck effect? answers a in south africa, much of the afrikaner population is descended from a small number of dutch colonists. in this population, this is an unusually high frequency of pseudoxanthoma elasticum (pxe), an elastic tissue disorder. b four white-tailed deer are introduced to a park in finland. thirty years after their introduction scientists compare the genes in the population and find that there is no variation. c during the industrial revolution, london's air became filled with soot. as a result, birds started eating more of the lighter moths because they were easier to spot than their darker counterparts. over time, the moth population changed so that there were more darker moths than lighter ones. d 10% of the population of american alligators in an area have the recessive trait albinism. a massive flood results in the death of 80% of the population. of the remaining population, 60% have the recessive trait of albinism.

Twin boys have girlfriends one of the couples have a baby would the dna of the lil baby be the same as the couples dna bc the boys are identical twins

Regarding most of the narrator’s story, which word best describes the tone?