16-6-2023 (LONDON) In a breakthrough discovery that has baffled minds for centuries, scientists from the University of Bristol’s School of Earth Sciences in the UK claim to have unraveled the age-old question of whether the chicken or the egg came first.
This eternal debate, pondered by school children and academics alike, has long eluded a definitive answer. However, the research team at Bristol may have cracked the puzzle.
While recent theories suggested that eggs were laid by dinosaur ancestors of chickens millions of years ago, even before chickens themselves existed, the new study proposes a different narrative.
According to the scientists, the earliest reptilian ancestors of chickens, which predate the existence of dinosaurs, might not have laid eggs at all. This revelation takes the chicken and egg conundrum to a whole new level.
Published in the journal Nature Ecology & Evolution, the study involved the examination of 51 fossil species and 29 living species, divided into two categories: oviparous (laying hard or soft-shelled eggs) and viviparous (giving birth to live young, similar to humans).
The research suggests that these early reptilian ancestors of chickens were viviparous, giving birth to live offspring instead of laying eggs.
Both the Bristol and Nanjing University teams believe that this finding is groundbreaking, emphasizing that the extended retention of embryos, where the mother retains the young before birth, provided exceptional protection for this group of animals. In essence, giving birth to live chickens was a safer reproductive strategy than laying eggs during that era.
Professor Michael Benton from the University of Bristol explained, “Before the amniotes, the first tetrapods to evolve limbs from fishy fins were broadly amphibious in habits. They had to live in or near water to feed and breed, as in modern amphibians such as frogs and salamanders. When the amniotes came on the scene 320 million years ago, they were able to break away from the water by evolving waterproof skin and other ways to control water loss. But the amniotic egg was the key.”
He further stated, “Our work, and that of many others in recent years, has consigned the classic ‘reptile egg’ model of the textbooks to the wastebasket.”
Professor Baoyu Jiang, the project leader, added, “This standard view has been challenged. Biologists had noticed many lizards and snakes display flexible reproductive strategies across oviparity and viviparity. Sometimes, closely related species show both behaviors, and it turns out that live-bearing lizards can flip back to laying eggs much more easily than had been assumed.”
While this study may have cracked the chicken and egg debate, or at least chipped away at it, it appears that both the chicken and the egg remain equally delectable culinary options.
The age-old mystery that has confounded generations has finally met its match in the labs of the University of Bristol, shedding light on the evolution and reproductive strategies of ancient creatures. It seems the chicken may have had the last word in this scientific saga, leaving us with a newfound understanding of our feathery friends and their egg-laying predecessors.
