Concept explainers
The Return of the Elephant Seals
Female elephant seals reach sexual maturity at 3 to 4 years of age and produce one pup each year. Elephant seals breed harem-style, with a single large bull typically monopolizing and inseminating 30 to 100 females. Although males reach sexual maturity at 5 to 7 years of age, few are powerful enough to acquire a harem until 7 to 10 years of age; some are never able to compete. Further, although the maximum life span is about 20 years for females and 15 for males, only about 1 in 5 survives beyond 5 years of age. These factors combine to produce a biotic potential of about 12% per year. But elephant seal populations virtually never reproduce at their biotic potential. Why not?
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Biology: Life on Earth with Physiology (11th Edition)
- Animals with a negative EPD for days to 90 kg (market weight) will produce offspring that reach market weight faster than offspring of parents with higher EPDs. TRUE or FALSEarrow_forwardPredict the F1 and F2 results of crossing a male fowl that is cockfeathered with a true-breeding hen-feathered female fowl. Recall that these traits are sex limited.arrow_forwardBecause the reproductive success of female Hanuman langurs (Semnopithecus entellus) is almost certainly lowered when a newly installed male kills their young infants, selection should favor countermeasures against infanticidal males. In this light, why might already pregnant females mate with a new male soon after a takeover even though they are not ovulating? What significance do you attach to the discovery that when mares are impregnated by stallions at stables away from their home locations, they will also copulate repeatedly with the males in their home stables upon their return?arrow_forward
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- Biology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStax