Scientists Tie 66-Million-Year Survival to Small Size and Generalist Diets
Updated
Updated · Livescience.com · May 24
Scientists Tie 66-Million-Year Survival to Small Size and Generalist Diets
3 articles · Updated · Livescience.com · May 24
A 66-million-year review of the asteroid extinction says the main survivors were small animals that could hide, needed less food, or lived in water, while 75% of species died.
Size alone was not enough: researchers say seed eaters, insectivores and detritus feeders fared better because sunlight was blocked for up to a decade, collapsing plant-based food chains.
Bird ancestors likely survived because they were small, flew well and raised fast-growing chicks; some turtles and fish endured in aquatic refuges, and durophagous turtles also benefited from prey that persisted.
Exceptions still puzzle scientists, including surviving night lizards with small litters and a 660-pound croc in Argentina, raising questions about Southern Hemisphere conditions and why mammals later became dominant.
If being small was the key to survival, how did a 660-pound land crocodile make it through the apocalypse?
If new research shows some ammonites survived the asteroid, was the impact not the true killer we thought it was?
With competing theories of volcanoes and global floods, how certain are we that an asteroid really killed the dinosaurs?
From Dinosaurs to Mammals: How the K-Pg Extinction Shaped Survival and Modern Biodiversity
Overview
The Cretaceous-Paleogene (K-Pg) extinction event, which happened 66 million years ago, wiped out about 75% of all species, including most non-avian dinosaurs, and dramatically reshaped life on Earth. Despite this catastrophe, some species, especially small mammals, managed to survive and thrive. Recent scientific discoveries are revealing new details about the specific traits and environmental factors that helped these groups endure the upheaval. By studying fossils and using advanced imaging techniques, researchers are uncovering how certain mammals adapted, providing important insights into why some species survived while others disappeared.