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Edible Insect Breeding Led to Larger but Not Necessarily Better Larvae

A pound of chicken will set you back a couple bucks.

Ground beef,maybe three to four dollars a pound.

But a pound of protein-rich dried mealworms could cost twice as much.

"The price per pound of mealworms is still relatively expensive." Juan A. Morales-Ramos is a research entomologist with the USDA in Stoneville,Mississippi.

But he says that cost might be coming down.

For eight years,he and his team have selectively bred mealworms, which are the larvae of a type of darkling beetle.

Their goal was to breed larger and larger worms - and they succeeded in nearly doubling the size of the larvae.

But doubling up came with an evolutionary tradeoff: larger larvae had fewer eggs, and their offspring weren't as hardy as the ancestral strain.

Still, generations are shorter in the worm worldmeaning it's faster to experimentand sequencing the genes of the selected strains might reveal new traits to breed for.

"We may be able to produce a superline of mealworms that grow faster and larger and probably produce more eggs,hopefully."The findings are in The Journal of Insect Science.

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