With its effects on fitness, transgenerational phenotypic modification can alter population demographics and community interactions. Mormon cricket eggs diapause in the soil for multiple years with duration largely dependent on degree days. Because Mormon crickets can be abundant in the landscape in one year and disappear suddenly the next, I asked: does parental nutrition affect the duration of egg diapause? To this end beginning in the ultimate nymphal instar, Mormon crickets were fed a diet high in protein, one equal in protein to carbohydrate, or a diet high in carbohydrates and the time for 50% of the eggs to develop after they were laid was measured. If parental nutrition affects egg diapause, then that change in sensitivity to heat might also alter the relationship between embryonic development rate and temperature. I asked: does parental nutrition affect embryonic development rate as a function of temperature? To this end, I manipulated grasshopper and Mormon cricket densities in field cages, collected eggs, and measured optimal temperature, maximum development rate, and thermal breadth for embryonic development. Mormon crickets fed high protein diet laid eggs with shorter diapause. Consistent with this result, those housed with more grasshoppers to eat laid eggs that had a faster maximum development rate, whereas those without grasshoppers had eggs with broader thermal breadth. Interestingly, doubling of Mormon cricket density caused eggs to develop in nearly half the time. With thinner densities or less protein available, parents spread their bet-hedging out and progeny spent longer times as eggs in the soil.
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