Hospital data shows that human infants born with an intermediate birth weight have a better chance of survival than those that weigh much less or much more. Larger than normal babies may have a difficult delivery, while smaller than normal babies may not be fully developed. What type of selection is occurring? Is the variability in birth weight in human populations increasing or decreasing?
What will be an ideal response?
This is stabilizing selection. As generations pass and the intermediate birth weight is favored, there would be a decrease in variability.
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Excreting ammonia directly into the environment (select all correct choices):
A. is energetically inexpensive. B. requires high volumes of water. C. is energetically expensive. D. requires little water. E. converts it into a less toxic form.
Compare and contrast a single, weak contraction of a muscle fiber, a twitch summation, and tetanus
What will be an ideal response?
34.4 The Hypothalamus and Pituitary Gland Fill in the blank(s) with the appropriate word(s)
The term reproductive isolation mechanism refers to ____
a. specific areas where males compete or display for females b. the process by which sexual selection evolves within a population
c. a blockage of gene flow between populations d. the inability of a species to continue reproduction e. legal limits to procreation