Me ! darwin hypothesized that there are definite steps to natural selection. consider the model of bacterial resistance to antibiotics. how would darwin explain step i? question 1 options: bacteria adapt to environmental changes. some bacteria alter their dna in response to environmental changes. in any population, some individuals are weaker than others. in any population, genetic variation exists.

What are some possible short and long term medical concerns for crew members on longer space exploration trips

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2

Elephants in the savanna regions of africa dig holes in dried up river beds to reach water lying just below the surface. these holes provide drinking water for other animals as well. so, without the elephants, many animals might otherwise die from lack of water during the dry season. the location in which the elephants live is an example of a/n and the role they play in creating water holes is an example of a a) ecosystem; habitat b) community; niche c) habitat; niche d) niche; habitat