Scientists at the University of Bristol may have finally cracked the age-old question of whether the chicken or the egg came first. Their study, published in Nature Ecology & Evolution, suggests that the chicken’s reptilian ancestors were viviparous, meaning they gave birth to live animals rather than laying eggs. The research implies that, in ancient times, birthing live young provided better protection, suggesting that live-born animals like chickens came before eggs.
The study examined 51 fossil species and 29 living species, categorizing them into egg-laying (oviparous) and live-bearing (viviparous) groups. The findings challenge traditional views about reptile evolution, as it turns out live-bearing lizards can revert back to laying eggs more easily than once thought.
The research indicates that early animals evolved to retain their embryos before birthing them, making live birth a safer option. As Professor Michael Benton from Bristol explained, live birth may have evolved before the amniotic egg, suggesting that the chicken (or its ancestors) came first.
This discovery sheds new light on evolutionary history and provides a possible answer to one of the oldest debates in science. However, the discussion continues, as this theory presents another perspective on how animals adapted over time.
