so closely related, in fact, that some scientists continue to argue their true familial ties. Physical differences between the snakes are minute, and include slight, but fairly consistent, variations in color pattern and scalation. But it is the reproductive preferences of these subspecies in the wild that poses perhaps the greatest argument for elevation of each to specific rank. Though interbreeding yields healthy offspring in captivity, there is an apparent reluctance between subspecies to mate in the wild, despite overlaps in the range of each. The ambiguities in their life histories yield two camps of thought—“splitters” who opt to maintain their sub-specific distinction, and “lumpers” who regard both races as a single species.
When viewed collectively, the species is a habitat generalist, capable of thriving in ecosystems spanning a variety of elevations—from sea level mangrove swamps to lower mountain forests sometimes as high as 3,000 feet. Its natural range extends to areas of both tropical and temperate climes—from semi-arid grasslands and deserts to wetlands of abundant rainfall. Regardless of where they are found, these pythons normally utilize the full gamut of natural features in an area, frequenting burrows, trees, rocky outcroppings, riparian zones, open water, and disturbed lands. In so doing, the snakes exercise their astonishing ability to swim, climb, and contort their bodies to meet the demands of the landscape. They are aided, of course, by tools forged over time through evolution: a supple skeleton, sinewy layers of muscle, and strong prehensile tails.
The species can adapt surprisingly well to hostile environmental conditions. In the northernmost reaches of its range, for instance, pythons are able to endure harsh winters during three-to-four-month periods of hibernation. In areas of constant inundation, the heavy-bodied pythons prove semi-aquatic in nature, comfortably spending significant time maneuvering their bulk both above and below the surface of the water. Pythons have also been known to persist in both disturbed and human environments, though it has been noted by some that they fare best amidst more natural habitats. And though it is also not their preferred haunt, pythons can even tolerate exposure to salt water for short periods of time while they comfortably navigate coastal waters.
Indian pythons and Burmese pythons occupy fairly distinct ranges south of the Himalayas. The former occupies nearly the entire South Asian subcontinent, where it is found primarily across large swaths of Pakistan, India, Nepal, and Sri Lanka. By contrast, Burmese pythons are generally encountered further east along a continuous range from northeastern India to southern China, with smaller, isolated populations also persisting in Nepal and on the islands of Java, Bali, Sumbawa, and Sulawesi. The details of natural distribution and biology are only partly known—informed by a limited collection of observations and studies from the field. But over the years, the study of captive animals has helped shed light upon the life histories of many snakes—particularly the Burmese python.
Hatching from the egg at only twenty inches, Burmese pythons experience one of the fastest growth rates known among snakes. During their first year of life, some can grow half a foot per month—particularly if fueled by regular feedings. Pythons reach sexual maturity sometime between reaching five and eight feet in length, a goal which can take as few as two to three years to achieve. The pace of growth slows gradually with age, but nonetheless permits both sexes to attain double-digit lengths. The females, however, typically dwarf their mates—sometimes reaching the length of a stretch limousine and tipping the scales at several hundred pounds.
To accommodate such growth, Burmese pythons readily consume any meal that satisfies their hunger. Diet is generally restricted to warm-blooded terrestrial animals, leaving a wide variety of potential prey on the menu. The python’s prowess at capturing, constricting, and consuming large prey has made it a staple of wildlife documentaries. But in addition to mind-boggling meals of leopards, deer, and antelope, the python feeds upon a much greater spectrum of both large and small fauna that includes wading birds, rodents, porcupines, bats, and domestic livestock. Though mammalian and avian prey is clearly preferred, the snakes are ultimately opportunistic in their feeding—known to consume even the occasional lizard, frog, or toad.
Cryptic coloration and a predilection for slow, deliberate movements provide an effective strategy for pursuing a meal. Burmese pythons are ambush predators that patiently lie in wait for their prey to advance. Engaged in attentive repose, pythons silently gather data using a sophisticated array of serpentine gadgetry—a sensitive inner ear transmits minute vibrations on the ground, a forked tongue processes molecules of odor captured from the air, and a full network of facial pits detects slight changes in temperature nearby. It is unclear whether it is motion, sight, or smell (or some combination thereof) that triggers the snake to feed.
Whatever the cue, it commands near-instantaneous strikes—widening jaws bearing rows of wretchedly recurved teeth capable of ensnaring an unsuspecting passerby. This bite, though no doubt painfully alarming, is nonfatal. Lacking venom, Burmese pythons must subdue their meal by sheer force. Using its mouthful of sharp barbs to hold fast the unfortunate captive, the snake throws coil upon coil around the body of its victim, exerting ever-increasing amounts of intense pressure. So strong is this fatal embrace it can at once squeeze breath from the lungs and render the heart inert. After some time, when movement is no longer detected, the large constrictor slowly relaxes its vicelike grip to finally indulge its appetite.
Though people are fascinated by the size, girth, and predatory instincts of the Burmese python, it is in other respects a fascinating biological creature of inspired design. Their seamless camouflage and capacity for stillness are well-developed traits that serve them not only in ambushing prey, but also constitute an effective strategy for self-preservation. A strong, prehensile tail allows them to hoist, suspend, and cantilever their bulk into trees high above the ground. The series of thermal pits that accents their lips allows for continued monitoring of their surroundings—enabling the detection of even minute differences in temperature nearby. And like other primitive snakes, Burmese pythons boast conspicuous pelvic spurs, which aid them in the requisite tickling and grasping that accompany courtship.
The reproductive habits of several python species are well documented, partly thanks to observations in the field, and partly due to the frequency and ease with which they are bred in captivity. Burmese pythons show great variability in the number of eggs they lay. While most will typically produce several dozen eggs at a time, both single-digit clutches and those in excess of 100 have also been reported. In captivity, females can be induced to lay a clutch every year, but in the wild they are more likely to produce a clutch every two to three years. During the time necessary for gestation and incubation a female python will often forgo all food—a prolonged period of four to six months during which she grows increasingly lean. Once her eggs are laid, a female python will swaddle her unhatched progeny in a protective stack of body coils. Should the ambient air begin to cool around them, the vigilant mother will begin to repeatedly contract the muscles in her lengthy body in a rhythmic fashion. As temperatures drop, these full-body spasms will grow ever more rapid and her coils will grow taller and tighter in a bid to generate heat for her unborn young. It is a display of maternal dedication rarely found among other reptiles, and a feat relatively unknown among cold-blooded animals—for a short span of time, she is actually capable of regulating her own body temperature for the benefit of her offspring.
Many facets of the life history of the Burmese python remain poorly understood. The extent of their distribution in certain portions of their native range still remains uncertain and in need of further study. The social workings of these large creatures remain somewhat shrouded in mystery, though observations of captive pythons provides some evidence to suggest a clear hierarchy may exist—particularly with regards to courtship. Both the density of Burmese python populations and the relative impact of disease and parasites on them still require further investigation. Even the full reproductive mechanisms of this species remain in question—some evidence exists that females may be capable of producing clutches of genetically identical young asexually through a process known as parthenogenesis.
The longevity of Burmese pythons in the wild also remains a great unknown. What little can be speculated about their span of life can only be gleaned through records of captives, some
