In a long term study by the evolutionary biologists Endler and Reznick, they illustrated the effect of predation on life history traits by studying guppies with different predators: cichlids and killifish. The killifish preys mostly on immature, smaller guppies and cichlids pursue mature, larger guppies. They noticed that in river portions with only killifish, the guppies were larger than in
river portions with only cichlids. How did Endler and Reznick test whether these differences in life history traits were genetic?
What will be an ideal response?
The biologists collected guppies from both cichlid- and killifish-dominated streams. They reared the groups in separate aquariums under identical predator-free conditions. Two generations later, the groups continued to show the differences observed in natural populations. The researchers concluded that differences between guppies preyed on by different predators have a genetic basis.
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Experiments like those performed by Stanley
Miller in the 1850s demonstrated
a. that DNA forms readily and produces itself. b. that organic compounds required for life can form under artificial conditions. c. that prokaryotic cells can form under artificial conditions. d. that meteorites contain the building blocks of life. e. that reactions in hydrothermal vents synthesis organic molecules
Beaked whales feed at various depths, but they defecate at the ocean's surface. Nitrogen-rich whale feces deposited in surface waters supply nutrients for algae that are eaten by surface-dwelling fish. Which of the following best predicts what would happen if the whale population decreased?
A) There would be a reduction in surface nitrogen concentration, which would cause an algal bloom B) The surface fish populations would decline due to reduced populations of algae C) The remaining whales would accumulate mutations at a faster rate D) The remaining whales would be forced to forage in the deepest parts of the ocean
The structures and processes in a society that authoritatively make and carry out the society's policies and rules are referred to as:
A) ideas. B) ideologies. C) businesses. D) governments.
Social Darwinism is a(n):
A) idea that evolutionary competition in human society, as well as the natural world, weeded out the unfit and advanced humanity. B) belief that sacred authority called for hard work, saving, thrift, and honesty as necessary for salvation. C) set of movements and concepts related to ideas of transmutation of species or evolution. D) union of ideas from several social specialties which provides a widely accepted account of evolution.