November 2, 2024

Faster and Better: How a Group of Scaly, Legless Lizards Hit the Evolutionary Jackpot

Credit: SciTechDaily.comMore than 100 million years back, the ancestors of the very first snakes were small lizards that lived alongside other small, nondescript lizards in the shadow of the dinosaurs.Then, in a burst of development in form and function, the forefathers of snakes evolved legless bodies that might wriggle throughout the ground, extremely sophisticated chemical detection systems to track and find prey, and versatile skulls that allowed them to swallow large animals.Those changes set the stage for the magnificent diversity of snakes over the previous 66 million years, allowing them to quickly make use of brand-new chances that emerged after an asteroid effect wiped out roughly three-quarters of the worlds plant and animal species.Factors Behind Snake DiversificationBut what set off the evolutionary surge of snake variety– a phenomenon understood as adaptive radiation– that led to nearly 4,000 living species and made snakes one of evolutions biggest success stories?A large new genetic and dietary research study of snakes, from a global team led by University of Michigan biologists, recommends that speed is the response. Snakes progressed up to 3 times faster than lizards, with massive shifts in characteristics associated with feeding, locomotion and sensory processing, according to a research study recently published in the journal Science.A cat-eyed snake (Leptodeira semiannulata) in the Peruvian Amazon. In addition, they compiled a huge dataset on lizard and snake diets, examining records of stomach contents from 10s of thousands of preserved museum specimens.They fed this mountain of data into advanced mathematical and analytical designs, backed by huge amounts of computer power, to analyze the history of snake and lizard development through geological time and to study how different characteristics, such as limblessness, evolved.This multipronged method exposed that while other reptiles have developed lots of snake-like traits– 25 different groups of lizards likewise lost their limbs, for instance– just snakes knowledgeable this level of explosive diversification.Take Australias legless gecko, for example.A knob-tailed gecko (Nephrurus levis) from Shark Bay, Australia. The sudden emergence and subsequent dominance of blooming plants is another example.In the case of snakes, the singularity began with the nearly synchronised (from an evolutionary viewpoint) acquisition of elongated legless bodies, advanced chemical detection systems and flexible skulls.Those vital modifications allowed snakes, as a group, to pursue a much wider array of victim types, while concurrently allowing individual species to progress extreme dietary specialization.Today, there are cobras that strike with lethal venom, giant pythons that restrict their prey, shovel-snouted burrowers that hunt desert scorpions, slim tree snakes called “goo-eaters” that prey on snails and frog eggs high above the ground, paddle-tailed sea snakes that probe reef crevices for fish eggs and eels, and many more.”What I like about this study is how it incorporates hard-earned field and museum data with brand-new genomic and analytical approaches to reveal a basic biological truth: Snakes are extraordinary and frankly rather cool,” said co-lead author Sonal Singhal of California State University, Dominguez Hills, who began work on the task as a U-M postdoctoral scholar.Reference: “The macroevolutionary singularity of snakes” by Pascal O. Title, Sonal Singhal, Michael C. Grundler, Gabriel C. Costa, R. Alexander Pyron, Timothy J. Colston, Maggie R. Grundler, Ivan Prates, Natasha Stepanova, Marc E. H. Jones, Lucas B. Q. Cavalcanti, Guarino R. Colli, Nicolas Di-Poï, Stephen C. Donnellan, Craig Moritz, Daniel O. Mesquita, Eric R. Pianka, Stephen A. Smith, Laurie J. Vitt and Daniel L. Rabosky, 22 February 2024, Science.DOI: 10.1126/ science.adh2449The study was supported by numerous funding agencies, consisting of multiple grants from the U.S. National Science Foundation.

Credit: SciTechDaily.comMore than 100 million years back, the forefathers of the very first snakes were little lizards that lived alongside other small, nondescript lizards in the shadow of the dinosaurs.Then, in a burst of development in form and function, the ancestors of snakes evolved legless bodies that might slither across the ground, extremely advanced chemical detection systems to track and discover prey, and versatile skulls that allowed them to swallow big animals.Those changes set the phase for the magnificent diversity of snakes over the past 66 million years, enabling them to quickly make use of brand-new opportunities that emerged after an asteroid effect cleaned out approximately three-quarters of the worlds plant and animal species.Factors Behind Snake DiversificationBut what set off the evolutionary explosion of snake diversity– a phenomenon understood as adaptive radiation– that led to nearly 4,000 living types and made snakes one of developments greatest success stories?A large new hereditary and dietary research study of snakes, from a worldwide team led by University of Michigan biologists, recommends that speed is the response. In addition, they compiled a substantial dataset on lizard and snake diets, examining records of stomach contents from tens of thousands of maintained museum specimens.They fed this mountain of data into advanced mathematical and analytical models, backed by enormous amounts of computer power, to examine the history of snake and lizard evolution through geological time and to study how various characteristics, such as limblessness, evolved.This multipronged technique exposed that while other reptiles have actually developed many snake-like traits– 25 different groups of lizards likewise lost their limbs, for circumstances– only snakes skilled this level of explosive diversification.Take Australias legless gecko, for example.A knob-tailed gecko (Nephrurus levis) from Shark Bay, Australia. The abrupt emergence and subsequent dominance of flowering plants is another example.In the case of snakes, the singularity began with the almost synchronised (from an evolutionary perspective) acquisition of elongated legless bodies, advanced chemical detection systems and flexible skulls.Those essential changes enabled snakes, as a group, to pursue a much more comprehensive variety of prey types, while all at once making it possible for specific types to progress severe dietary specialization.Today, there are cobras that strike with lethal venom, giant pythons that constrict their victim, shovel-snouted burrowers that hunt desert scorpions, slender tree snakes called “goo-eaters” that prey on snails and frog eggs high above the ground, paddle-tailed sea snakes that penetrate reef crevices for fish eggs and eels, and lots of more.