Snakes eat other animals, and depending on the snake, the food can be mice, rats, rabbits, fish, frogs or even other snakes. Snakes do not chew their food. They swallow their prey whole. As of October 2022, Cincinnati biologist Bruce Jayne found that snakes do not dislocate their jaws to swallow big prey. A python's lower jaw is two bones joined by stretchy tissue, and just over 40 percent of its gape area is stretchy skin. Gape width, not body size, set how large a meal a Burmese python could take. After a big meal a snake does not need to eat again for a long time, and Burmese pythons can go four to six weeks between meals.

As of January 2018, Jayne had tested a guess made in 1950 by biologist H.W. Lissmann, that the muscle that shortens a snake's belly skin pushed a snake straight forward. He used electromyograms and high-definition video of boa constrictors, and found Lissmann had that main driver wrong. In rectilinear movement a snake moves forward in a straight line, flexing the skin of its belly. 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 January 2012, a team led by Davidson College biologist Michael Dorcas, with USGS, Virginia Tech and other scientists, reported that mammals had crashed in Everglades National Park after Burmese pythons took hold. As of January 2012, the team had counted live and road-killed mammals on night drives, and over 2003 to 2011 it traveled nearly 39,000 miles and compared results with surveys of the same roads in 1996 and 1997, before pythons were known to be established there. As of January 2012, they found that where pythons had lived longest, raccoons fell 99.3 percent, opossums 98.9 percent and bobcats 87.5 percent. As of January 2012, scientists thought Everglades mammals fell so fast partly because they were naive: they had never met a snake that large. As of January 2012, a USGS scientist compared it with Guam, where the brown treesnake took about 30 years to be linked to the loss of mammals and birds, against about 11 years for pythons in Florida.

As of August 2012, scientists tracked wild snakes with radio telemetry: a small transmitter inside the snake sends a signal at its own frequency, and a researcher uses an antenna and receiver to find it. As of August 2012, collars did not fit snakes, so a vet implanted the transmitter in the body cavity. As of April 2019, scientists used the Judas technique to find pythons that hide well in dense Everglades wetlands. The tagged snake goes to find a mate during the winter breeding season, and that leads researchers to other pythons, including large egg-bearing females. 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.

In cold weather snakes rest through the winter in a state called brumation, which is like hibernation, and snakes are cold-blooded, so their body temperature changes with the surroundings, and to survive winter they burrow below the frost line, the depth to which groundwater freezes, and often shelter together. As of August 2023, Tel Aviv University scientists had measured the resting metabolism of 156 lizards and snakes from 59 Israeli species in winter and summer. Animals measured in both seasons used 47 percent less oxygen in winter at 20 degrees Celsius and 70 percent less at 12 degrees. Cold alone may not explain it, because the animals may actively slow their bodies in the cold. As of March 2021, Iowa State University researchers had cooled checkered garter snakes to copy winter brumation, then tested hormones and resting metabolism before, during and after. After the cold spell, the snakes' resting oxygen use was lower than before at the same temperature.

As of November 2026, researchers in 2015 had reported an early Cretaceous fossil with both hind legs and tiny front legs, a burrowing predator that some called a four-legged snake. As of November 2019, a study of the fossil snake Najash found that legged snakes living nearly 100 million years ago still had a cheekbone, the jugal, that has almost vanished in modern snakes. As of October 2016, University of Florida researchers found that completely limbless snakes show more decay of a limb-building genetic switch, the Sonic hedgehog enhancer, than pythons and boas, which still keep tiny leg bones, a clue to how legs were lost step by step.

Words to know

• gape: mouth opening
• electromyograms: muscle-signal recordings
• naive: unfamiliar with danger
• brumation: winter dormancy
• enhancer: genetic switch