Biology Now, 2e

Fast Lizards, Slow Corals ■ 247

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the old West. During the late 1800s the American range bison

were hunted to the brink of extinction, leaving behind a bottleneck

population of only 1,091 individuals. The population has since

rebounded to about 500,000 bison. Unfortunately, almost all

of these bison are the descendants of these few individuals

crossbred with domestic cattle by ranchers. Scientists and

conservationists want to genetically test bison to find those of

pure bison origin to preserve the species. Only these, they argue,

should be called American range bison and be allowed to roam

free in the national parks as bison. They think hybrids should be

confined to farms and ranches, should be called “beefalo” rather

than bison, and should not be afforded the protection that pure

bison currently have. What do you think? Should bison tainted

with cattle genes be removed from free-range parks? Should the

government spend scarce conservation monies on genetic testing

and breeding efforts to preserve the pure bison population?

Investigate conservation efforts and the costs of genetically

testing and relocating bison to help you with your decision. Is

speciation at the hands of human beings now part of evolution

as we know it?

(^13) Researchers from the Smithsonian Institution were startled
to discover that the 3 species of Starksia blennies they had been
studying in the Caribbean islands were really 10 different species.
How could these researchers have thought that these 10 different
reef fish species were only 3 species?
Leveling Up
(^14) Write Now biology: adaptations Select an organism (other than
humans) that you find interesting. Research two adaptations of
your organism and describe them in detail. Explain carefully why
each of these features is considered an important adaptation
for its species. Discuss how a change in the environment might
change the usefulness of these adaptations.
(^15) Doing science The eastern and western meadowlarks are
very similar in morphology. Both are grassland species with some
overlap in their range in the upper Midwest, and each sings a
distinctly different song. Create a hypothesis as to whether these
are two different species or two populations of the same species,
and describe an experiment that would enable you to test your
hypothesis. What result would support your hypothesis, and what
result would cause you to reject your hypothesis?
(^16) What do you think? According to the Defenders of Wildlife
organization, there were 20–30 million American range bison in E^ D^ q^ M