Researchers have collected data from 868 bird species and showed that even when island birds can still fly, they’re edging towards flightlessness. Compared to mainland relatives, their flight muscles (the ones we eat when we tuck into chicken breasts) are smaller and their legs are longer.

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Researchers have collected data from 868 bird species and showed that even when island birds can still fly, they’re edging towards flightlessness. Compared to mainland relatives, their flight muscles (the ones we eat when we tuck into chicken breasts) are smaller and their legs are longer.