A few kinds of snakes, such as rattlesnakes and coral snakes, catch prey with venom that they inject through their fangs. As of April 2021, researchers in Japan had studied how venom, which some snakes use to catch prey, began. They compared the genes working in snake venom glands with those in the salivary glands of other animals and found a shared network of about 3,000 housekeeping genes, and they suggested venom glands built on machinery that saliva glands already used. As of March 2005, a University of Melbourne study had compared the amino acid sequences of snake venom proteins with ordinary body proteins, and it found that venom proteins were recruited from other protein families at least 24 times in the evolution of snake venom, and two kinds of venom proteins appear to be changed saliva proteins. A wild snake is best left alone: it will usually go its own way. If one is near a home, a grown-up can call animal control.
Some snakes have heat-sensing pits on the sides of the head that sense the warmth given off by warm-blooded prey. A snake's pit organ, which sits between the eye and the nostril in rattlesnakes, can sense infrared radiation, which is heat, and it gives the snake a picture of its surroundings made from infrared radiation, a thermal image. As of March 2010, scientists had studied how a pit viper's heat pit works, and in rattlesnakes the gene for a heat-sensitive channel called TRPA1 was about 400 times more active in the nerve cells that serve the pit than in other nerve cells, though snakes without pits did not show this difference, so TRPA1 was named an infrared receptor. As of November 2026, University of Houston researchers reported in 2020 that cells in the pit organ membrane may work as a pyroelectric material, turning heat from warmer animals into electrical signals.
Parthenogenesis means young develop from an egg without a father. As of September 2012, a University of Tulsa biologist had reported the first known case in the wild, and DNA tests of litters from wild-caught copperheads and cottonmouths showed that a male's part in them was "infinitesimally small", and scientists still do not know what prompts it. The flowerpot snake, a tiny burrower often mistaken for an earthworm, is a species of only females. As of May 2025, a study led by the University of Texas at Arlington had mapped its genome and found 40 chromosomes in three sets, called triploidy. Scientists hope to learn how its eggs develop without a father.
As of April 2015, a team led by John Wiens warned that anatomy alone can mislead when building family trees, and it added DNA to the data. Old museum specimens help build snake family trees. As of September 2023, University of Kansas researchers had combined degraded mitochondrial DNA from museum mud snakes with fresher DNA from 4,800 nuclear loci in field-collected snakes, and they made the most complete family tree of the mud snake family, showing which species branched off and roughly when. As of August 2024, a study of the cobra-and-coral-snake family, Elapidae, used genomes of 65 snakes and data from 434 more species to build a tree, and it found the family began in Asia, not Africa as many had thought, because earlier studies lacked enough data. An international team built the largest, most comprehensive evolutionary tree of snakes and lizards, covering nearly 1,000 species, and linked snakes' big spread of kinds to the last 66 million years.
In sidewinding, a snake bends in waves both side to side and up and down, and sidewinder rattlesnakes cross hot desert sand with a sideways move that keeps little of the body on the sand at once. As of October 2014, Georgia Tech researchers had measured how sidewinder rattlesnakes climb sandy slopes. They do not dig deeper as the slope steepens, and instead they put more of their body on the sand at each moment, which lowers the chance of slipping. As of October 2014, to test sidewinders on sand slopes without bringing venomous animals into the lab, the team built a test slope in a shed at Zoo Atlanta and hauled in sand from Arizona. As of October 2014, only sidewinders climbed well: twelve of 13 other kinds of pit viper failed on sandy slopes of even 10 degrees.
Five kinds of snakes can glide through the air from tree to tree, in southern and southeast Asia. As of June 2020, flying snakes were known to ripple as they glide, and a Virginia Tech study had filmed more than 100 glides of paradise tree snakes, then built a 3D model. With the waves switched off in the model, the snake tumbled, and with them on, its body stayed steady and glided farther. The study showed the undulation helps stabilize the snake in the air. As of June 2020, Virginia Tech researchers described how a paradise tree snake begins a glide by curving into a J-shaped loop and springing up and out. It then flattens its body everywhere but the tail, so the body works like a morphing wing that makes lift and drag as air flows over it, while waves run down its length. Paradise flying snakes launched from a tower typically landed about 10 meters away, and one glided as far as 21 meters.
As of February 2018, Harvard engineers had made a soft crawling robot with no rigid parts by copying snake scales. A flat plastic sheet cut in kirigami patterns wraps an inflatable tube, and when the tube swells, the cuts pop up and grip the ground, and when it shrinks they fold flat and the robot moves forward. Trapezoid cuts, most like snake scales, gave the longest stride. Snakes slither partly because of friction from their belly scales. As of June 2009, a study from New York University and Georgia Tech had found that the scales are oriented so a snake resists sliding toward its tail and flanks. Georgia Tech scientists studied desert sidewinder rattlesnakes climbing sand dunes and built a snake-like robot that could climb nearly any hill. Engineers also studied variable kingsnakes, which live in deserts and pine-oak forests, and built a snake robot with a suspension in each body segment that climbs large steps, aiming at search and rescue robots.
Words to know
- parthenogenesis: birth without father
- genome: full DNA set
- triploidy: three chromosome sets
- kirigami: cut paper-folding
- mitochondrial: cell-power
