Elephants Are Evolving Without Tusks Thanks to Poaching

iStock.com/LeighGregg
iStock.com/LeighGregg

Natural selection can take millions of years to shape a gene pool, but in parts of Africa, the extreme pressures of poaching may have changed elephants in just a few decades. As National Geographic reports, more tuskless elephants have emerged in regions where their ivory has made them a target.

Elephant poaching has long been in a problem Africa, but the crisis reached a fever pitch during Mozambique's 15-year civil war. Between 1977 and 1992, 90 percent of the elephants living in the country's Gorongosa National Park were slaughtered for ivory used to fund the conflict.

The diminished numbers aren't the only thing that looks different about Gorongosa's elephants today. Poachers often kill male elephants first because they have bigger tusks, and once they're eliminated, the hunters will go after females. Typically, about 2 to 4 percent of all female African elephants never develop tusks—but among female elephants that survived Mozambique's civil war, that number is 51 percent. The effects of poaching can also be observed in the next generation. Roughly 32 percent of female elephants born after 1992 are tuskless.

The trend can be seen in other parts of Africa where poaching has ravaged elephant populations. In Ruaha National Park in Tanzania, elephant behavior researcher Josephine Smit has observed that over one fifth of female elephants older than 5 years lack tusks. Tusklessness rates reach about 35 percent in females over 25.

The statistics are even harder to ignore in South Africa's Addo Elephant National Park, where tuskless animals made up 98 percent of all female elephants in the early 2000s. South Luangwa National Park in Zambia, Lupande Game Management Area in Zambia, and Queen Elizabeth National Park in Uganda each reported higher-than-average rates of tusklessness immediately following the ivory wars of the 1970s and '80s.

Though poaching is on the decline thanks to bans on the ivory trade and other conservation efforts in Africa, its impact can still be felt. In East Africa, the elephant population was nearly halved between 2008 and 2018. The establishment of wildlife preserves, DNA tracing, and GPS tracking are just a few of the ways conservationists are working to crack down on poachers and restore the species.

[h/t National Geographic]

No Venom, No Problem: This Spider Uses a Slingshot to Catch Prey

Courtesy of Sarah Han
Courtesy of Sarah Han

There are thousands of ways nature can kill, and spider species often come up with the most creative methods of execution. Hyptiotes cavatus, otherwise known as the triangle weaver spider, is one such example. Lacking venom, the spider manages to weaponize its silk, using it to hurl itself forward like a terrifying slingshot to trap its prey.

This unusual method was studied up close for a recent paper published in the Proceedings of the National Academy of Sciences by researchers at the University of Akron in Ohio. They say it's the only known instance of an animal using an external device—its web—for power amplification.

Hyptiotes cavatus's technique is simple. After constructing a web, the spider takes one of the main strands and breaks it in half, pulling it taut by moving backwards. Then, it anchors itself to a spot with more webbing in the rear. When the spider releases that webbing, it surges forward, propelled by the sudden release of stored energy. In the slingshot analogy, the webbing is the strap and the spider is the projectile.

This jerking motion causes the web to oscillate, tangling the spider's prey further in silk. The spider can repeat this until the web has completely immobilized its prey, a low-risk entrapment that doesn’t require the spider to get too close and risk injury from larger victims.

The triangle weaver spider doesn’t have venom, and it needs to be proactive in attacking and stifling prey. Once a potential meal lands in its web, it’s able to clear distances much more quickly using this slingshot technique than if it crawled over. In the lab, scientists clocked the spider’s acceleration at 2535 feet per second squared.

Spiders are notoriously nimble and devious. Cebrennus rechenbergi, or the flic-flac spider, can do cartwheels to spin out of danger; Myrmarachne resemble ants and even wiggle their front legs like ant antennae. It helps them avoid predators, but if they see a meal, they’ll drop the act and pounce. With H. cavatus, it now appears they’re learning to use tools, too.

[h/t Live Science]

Plano, Texas Is Home to a Dog-Friendly Movie Theater That Serves Bottomless Wine or Whiskey

K9 Cinemas
K9 Cinemas

For dog owners in Plano, Texas, movie night with Fido no longer just means cuddling on the couch and browsing Netflix. The recently opened K9 Cinemas invites moviegoers—both human and canine—to watch classic films on the big screen. And the best part for the human members of this couple? Your $15 ticket includes bottomless wine or whiskey (or soft drinks if you're under 21).

The theater operates as a pop-up (or perhaps pup-up?) in a private event space near Custer Road and 15th Street in Plano. Snacks—both the pet and people kind—are available for $2 apiece. Dogs are limited to two per person, and just 25 human seats are sold per showing to leave room for the furry guests.

Pet owners are asked follow a few rules in order to take advantage of what the theater has to offer. Dogs must be up-to-date on all their shots, and owners can submit veterinary records online or bring a hard copy to the theater to verify their pooch's health status. Once inside, owners are responsible for taking their dog out for potty breaks and cleaning up after any accidents that happen (thankfully the floors are concrete and easy to wipe down).

While many of the movies shown are canine-themed—a recent screening of A Dog's Journey included branded bandanas with every ticket purchase—they also hold special events, like a Game of Thrones finale watch party (no word on how the puppers in attendance responded to Jon Snow finally acknowledging what a good boy Ghost is).

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