Amazing stuff!
"Roughly 128 million years ago snakes suddenly burst into an abundant existence on Earth, eventually diversifying into the 4,000 or so species we see today.
Yet their prevalence can't be solely attributed to their most obvious characterizing traits: abandonment of limbs and body elongation. While 25 different groups of lizards are limbless, no other type of reptile has reached the explosive level of diversity seen among snakes. ..."
"A study of more than 60,000 museum specimens of snakes and lizards worldwide reveals that snakes stand out alone in the evolution of reptiles. ...
The team of international scientists ... explain that a “burst of innovation in form and function” enabled the ancestors of snakes to move with legless bodies, develop chemical detection systems to find and track prey, and grow flexible skulls to swallow large animals. The changes set the stage for snake diversification and survival, particularly after an asteroid impact wiped out about three-quarters of Earth’s plant and animal species. ...
“Snakes are like the Big Bang ‘singularity’ in cosmology – a dramatic expansion of diversity in species and their ecologies, linked to some event that might have occurred early in the evolutionary history of snakes.” ..."
“Snakes are like the Big Bang ‘singularity’ in cosmology – a dramatic expansion of diversity in species and their ecologies, linked to some event that might have occurred early in the evolutionary history of snakes.” ..."
From the editor's highlights and abstract:
"Editor’s summary
Snakes are important members of today’s ecosystems and, together with lizards, make up one-third of the vertebrate biota. Their iconic status largely comes from their morphology and role as impressive and varied predators. Title et al. looked at the evolution of the group and used a large number of natural history diet observations to explore their role in ecosystems. They found that a pulse of evolutionary innovation that occurred at the origin of snakes more than 150 million years ago led to an expansion of diet in squamate reptiles, which had cascading impacts on ecosystems that persist today. ...
Abstract
Snakes and lizards (Squamata) represent a third of terrestrial vertebrates and exhibit spectacular innovations in locomotion, feeding, and sensory processing. However, the evolutionary drivers of this radiation remain poorly known. We infer potential causes and ultimate consequences of squamate macroevolution by combining individual-based natural history observations (>60,000 animals) with a comprehensive time-calibrated phylogeny that we anchored with genomic data (5400 loci) from 1018 species. Due to shifts in the dynamics of speciation and phenotypic evolution, snakes have transformed the trophic structure of animal communities through the recurrent origin and diversification of specialized predatory strategies. Squamate biodiversity reflects a legacy of singular events that occurred during the early history of snakes and reveals the impact of historical contingency on vertebrate biodiversity."
Snakes: An Evolutionary Winner (original news release) Study published in Science reveals a burst in serpentine form and function reshaped vertebrate diversity
Snakes (red) have far more diverse diets than their close lizard relatives (blues). Each dot represents one of 1,314 species and size indicates diversity of food within species.
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