Snakes, in general, do not win any parenting awards. The snake species that lay eggs usually plop their clutch in a hole, cover them with dirt, then slither off hoping for the best. Most of the 30 percent or so of snake species that give live birth don’t give much thought to their offspring, either. But as Joshua Rapp Learn at National Geographic reports, a new study has found that at least one species of egg-laying python does do a bit of parenting, showing that a mother’s love has no bounds (even if it does have fangs).
Graham Alexander, a reptile researcher the University of the Witwatersrand in Johannesburg, South Africa, spent seven years observing southern African pythons, which can grow up to 16 feet long, weigh 130 pounds and take down animals as large as antelope. Using radio transmitters and cameras installed in the aardvark burrows the snakes use for nesting, he observed 37 pythons in the Dinokeng Game Reserve, according to a press release about the study, and over the course of the study eight of those snakes laid eggs.
Using infrared cameras inside the burrows, Alexander recorded the mother snakes' behavior. One change is that the mother snakes turn from their normal mottled brown to a dark black, which probably helps them absorb more warmth from the sun. Since the snakes are unable to raise their body temperature through their metabolism, they bask in the sun, raising their temperature as high as 104 degrees. They then slither back into their burrows and coil around their egg clutch, keeping it warm throughout the night. After the snakelets are born, they do the same thing, keeping their 40 to 50 babies warm for about two weeks before saying sayonara.
This is the first time an egg-laying snake has been shown to give a hoot about its young. The study appears in the Journal of Zoology.
So why does this particular snake hug its children when all the others don’t? Learn reports that it may have to do with overeating. The python young are still packed full of undigested egg yolk when they are born. That makes them sluggish and not very mobile, making them easy snacks for predators in the bush. Keeping them warm and safe helps them digest the yolk until they are mobile enough to start hunting on their own.
All that slithery love, however, comes at a cost. Ed Stoddard at Reuters reports that during the entire child-rearing process the mother snake does not hunt and can lose up to 40 percent of its body weight. In fact, according to the press release, some female pythons starve after bearing children, worn out by the process. That’s why pythons will only lay a clutch once every two to three years instead of annually. “There must be an evolutionary advantage, because if the mother is forgoing feeding all that time it’s obviously a big cost to her, so there must be some benefit that outweighs that cost,” Alexander says.
Learn reports that geography may also have something to do with the mothering. The study site is near the southern range of the snakes, and close to colder climates. Pythons only incubate if the temperature is 82 degrees or lower, otherwise they will be stillborn or deformed. The snake hug may be a way to ensure the babies stay warm enough to develop properly.
The study shows that biologists still have more to learn about the way reptiles mate and raise the next generation. "Research is showing that snake reproductive biology is far more complex and sophisticated than we previously thought, and there is a range of behaviors that have been recorded in several species that can be classed as maternal care,” Alexander says in the release. “For example, biologists are discovering that females of many types of rattlesnakes show maternal care of babies. In some species, mothers appear to even cooperate by taking shifts to look after young. But all these species are live bearing—our python is the first egg laying species that has been shown to care for its babies."
So next time you see something slither across your path, be kind to your scale-bellied friend. That snake may be somebody’s mother.