12 things to know about rattlesnakes
Coiled defensively, head erect and tail vibrating, an endangered rattlesnake commands respect. These poisonous snakes have developed one of nature’s most spectacular warning systems in their segmented rattles. But as we’ll see, their powerful bites aren’t the only thing rattlesnakes have for them.
1. Scientific names for rattlesnake refer to musical instruments.
All 36 rattlesnake species are native to the Americas, with an overall range extending from southern Canada to central Argentina and concentrated in the American Southwest. They can survive in all kinds of habitats where their prey – birds, rodents, amphibians and other small animals – are abundant. Rattlesnakes belong to two genera of the subfamily Crotalinae (pit vipers): Rattlesnake, from the Greek word for castanet; and Sistrurus, invoking an ancient Egyptian musical instrument. Both genus names undoubtedly refer to the characteristic rattles of snakes.
2. The venoms in rattlesnake bites are highly variable, even among members of the same species.
Every type of rattlesnake bite venom exists complex cocktail loaded with different enzymes, toxins and other compounds. Hemotoxins, which destroy capillary walls and impede blood flow, are key ingredients in most of them. Neurotoxins, which attack the victim’s nervous system and cause seizures or paralysis, are another weapon. The composition of the venom can be extremely variable among individuals of the same species; for example, some timber rattlesnakes living in the southern United States have more neurotoxic venom than their northern counterparts.
3. Rattlesnakes bite with movable fangs.
Cobras, mambas and other snakes inject their venom into their victims through a pair of protoglyphs, or fixed, fangs near the front of their mouth. These snakes must bite and cling to their prey to deliver the poisonous punch. Rattlesnakes take a different approach. Like the Copperheads and Old World vipers, they have solenoglyphs fangs, which can actually swing forward and allow the rattles to strike quickly, inject venom, and then recoil. When the fangs are not in use, they are pulled back and pressed against the roof of the snakes’ mouths.
4. Most rattlesnake bites are not fatal.
Rattlesnakes are the first supplier of poisonous snakebites to North America. About 7,000 to 8,000 people are bitten each year, but thanks to effective antivenoms, only five or six the bites are fatal.
5. Disembodied rattlesnake heads may still bite.
In 2018, a man from Corpus Christi, Texas, found a Western Diamondback Rattlesnake in his backyard and beheaded it with a shovel. Imagine his surprise when the head bit his hand. Man has lived, but there have been cases of fatally detached heads poisoning people; the bite reflex in many poisonous snakes remains active after the animal’s death.
6. The eastern diamondback rattlesnake is the largest poisonous snake in North America.
Native to the southeastern United States, the eastern diamond back can grow up close 8 feet long and weigh over 15 pounds. It is the largest rattlesnake in the world and the largest poisonous snake on the North American continent.
7. Rattlesnakes begin to grow rattles after they are first shed.
Each rattlesnake is born with a nubby scale at the end of his tail called a pre-button. After the snake’s first skin shedding, the pre-pimple is replaced with a button, a larger scale in the shape of an hourglass. Later sheds add hollow, nested segments of keratin to the end of the tail. By vibrating the segments, the snakes create its distinctive clicking sound. Although it is a myth that rattlesnakes must vibrate their cocks before striking, they use their rattles to warn approaching animals or people.
8. The number of rattle segments has nothing to do with the age of the rattlesnake.
Popular myth suggests that each rattle section represents a year in the animal’s life. In reality, a rattlesnake can lose multiple times and gain multiple rattle segments in a single year. Segments can also wear out and rupture over time.
9. Rattlesnakes do not lay eggs.
Like anacondas, rattlesnakes are ovoviviparous: they produce eggs that hatch inside their body and give birth to live, fully formed young. Depending on the species, a rattlesnake litter can include anywhere one to 25 infants.
10. Not all rattlesnake species have a rattle.
Crotalus catalinensis, the Santa Catalina rattlesnake, evolved into without rattling. He lives on Isla Santa Catalina, a small island in the Gulf of California. Although it belongs to the same genus as diamondbacks and wood rattles, the ancestors of snakes may have lost their appendages because there are fewer predators and large mammals trampling on the island to warn with threatening noises.
11. Rattlesnakes help plants by distributing seeds.
In one 2018 study, the researchers looked at the guts of 50 dead rattlesnakes kept in museums. They found 971 plant seeds which were probably carried by the rodents that the snakes had eaten. When a rattlesnake devours an unfortunate mouse, the seeds it carried in its cheeks pass through the snake’s digestive tract intact. By pooping the seeds, snakes help restore plant growth to their habitat.
12. Benjamin Franklin admired the wooden rattles.
Benjamin Franklin believed that the rattlesnake embodied only American diplomacy and harshness. “She never hurts until she has generously warned, even to her enemy, and warned him of the danger of stepping on her,” he wrote in a Pennsylvania newspaper in 1775. “Am I wrong, Sir, in thinking that this was a strong image of America’s temper and conduct?”
He also noted that, like all snakes, wooden rattles do not have eyelids, which makes them naturally vigilant. “It can therefore be seen as an emblem of vigilance,” Franklin wrote.
Rattlesnakes later became symbols of America’s War of Independence. Christopher Gadsden, a colonel from South Carolina, designed a personal flag for display on five ships belonging to the Continental Army. The bright yellow banner featured a coiled rattlesnake emblem and the caption “Don’t step on me”. He remain popular among supporters of a smaller federal government today.