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Biology

Parental Investment and Offspring Sex Ratios in Red Deer

Quick fact

In red deer, hinds in good condition are more likely to give birth to sons, while those in poorer condition more often have daughters. This pattern is a classic example of the Trivers-Willard hypothesis, where maternal investment is biased toward the sex that offers the greatest reproductive payoff.

Why this is interesting

Why would a mother red deer sometimes produce more sons and sometimes more daughters? What does this tell us about her hidden strategy?