The ecological origin and early evolution of snakes has been the focus of multiple research fields for many years, making them one of the most persistent and controversial topics in biology. Conflicting ecological hypotheses for early snakes, including aquatic, terrestrial, hemimetaplastic, metaplastic, and even multiple habitats, have been proposed based on analyzes of various traits. To address the lack of well-preserved snake fossils, a team of scientists from the University of Helsinki and the University of Toronto Scarborough applied an alternative hypothesis based on high-definition brain reconstructions of modern snakes and lizards. Their predictive model revealed a burrowing lifestyle with opportunistic behavior in the origins of the earliest snakes.
Snakes are fascinating creatures, making up about one-eighth of all vertebrates found on land.
They come in all shapes and sizes and have adapted to different lifestyles, including living underground, on land, underwater, and in trees.
However, the early evolution of snakes and their changes in morphology over time have long been debated in the field of biology.
To solve this mystery, Dr. Simone Macri and colleagues at the University of Helsinki used a different method of studying snake evolution.
“Rather than relying on rare old fossil remains to learn about snake history, thanks to modern image processing and analysis tools, we have been able to examine the brains of living reptiles and travel back in time.” said Dr. Macri.
Researchers used high-resolution 3D models of modern lizard and snake brains to reconstruct the brain shapes of early snakes and found they were perfectly adapted to life underground .
Nevertheless, early snakes also exhibited versatile behavior, as evidenced by a mix of different features and complex patterns in brain morphology. This may reflect differences in what they eat, how they use different environments below and above ground, and their abilities. Look for food.
“What’s really interesting is that this study is not just about snakes,” said Dr. Nicholas Dipoi, also from the University of Helsinki.
“It also shows how we can learn about other animals whose history is a bit of a mystery because we lack fossils to study.”
“By examining both modern and past animals, along with vital organs such as bones and brains, scientists are assembling stories about how these animals changed and evolved over time. can do.”
This study highlights important lessons for the field of biology. Solving the mysteries of animal evolution goes beyond analyzing bone remains.
“Our study demonstrates the power of combining Rivian and extinct species, soft tissue reconstructions, and osteological features in tracing the deep evolution not only of snakes but also other groups for which fossil data are lacking. “, the authors concluded.
their paper It was published in the magazine scientific progress.
_____
Simone Macri other. 2023. Reconstructing the origin and early evolution of the snake brain. scientific progress 9(39); doi: 10.1126/sciadv.adi6888