A passion for the natural world drives many of our adventures. And when we’re not outside, we love delving into discoveries about the places we live and travel. Here are some of the best natural history links we’ve found this week.
Using silent e-bikes to catch poachers: Poachers in Africa listen for the noisy motorbikes that rangers typically use. These are audible from two kilometres away and give the poachers plenty of time to escape. So now rangers across the continent have begun to switch to silent, off-road e-bikes.
The exact location of the bikes is a secret, but they are now in 127 parks across Africa. The bikes charge via solar power at mobile charging points. This has allowed rangers to silently track poachers for weeks at a time.
The bikes are usable on plains, in forests, and in jungles. So far, they have stopped poaching attempts on several species of duiker. Although none of the tiny antelopes are at risk, they are essential prey for endangered predators.
Protecting beachgoers without killing sharks
Drones spot sharks that get too close to busy beaches: Queensland, Australia’s state government is trialing a new shark safety program. For years, they relied on nets and baited drumlines to protect beachgoers from sharks.
These methods are effective but also harmful. Last year, they caught 958 animals, including 798 sharks. Unfortunately, 70% of them died. Dolphins, dugongs, and turtles also perished in the protective equipment.
So instead, they are now using camera-equipped drones to monitor sharks. The drones fly at an altitude of 60m, and when the pilot detects a shark, it drops down to identify the size and species. If the shark is a danger, they evacuate the beach while lifeguards monitor the animals from personal watercraft. An added bonus of drones is that they can drop life-saving equipment to beachgoers struggling in the water.
Photo: Shutterstock
Bear skins were the original key to northern survival
People used bear skins 320,000 years ago: Researchers have uncovered cut-marked bones of cave bears in Lower Saxony, Germany. The 320,000-year-old bones came from a Middle Pleistocene site at Schöningen.
Cut marks usually signify that the animal was used for meat, but these marks are on the hand and foot bones. “There is hardly any meat to be recovered from hand and foot bones,” points out palaeontologist Ivo Verheijen.
Rather, such fine and precise cut marks suggest a careful stripping of the skin. This implies that the ancient people of northern Europe used bear skins to survive cold winters.
Bears’ winter coats are particularly thick because they need to keep the animals warm during hibernation. They have long outer hairs and a layer of dense, short hair. “The use of bear skins is likely a key adaptation of early humans to the climate in the north,” said Verheijen.
Genital spines help male wasps survive: Male wasps do not have venom-injecting stingers. Instead, they have a pair of spines that evolved with their reproductive systems. The genital spines contain no venom, but the wasps use them to stab predators in the face.
But how much damage can these genital spines do? Researchers put wasps together with different species of frogs in a lab setting. With pond frogs, the spine pricks did not help, and all 17 wasps were eaten.
However, with tree frogs, the wasps used their spine to pierce the frog’s mouth. Though the spines don’t cause serious damage, they cause enough pain so that the startled predator drops the wasp or retreats.
Photo: Shutterstock
Sure enough, domestic cats are still pretty wild
When were cats first domesticated? Nearly 10,000 years ago, humans settled in the Fertile Crescent, the region around the Tigris and Euphrates rivers. Soon, hunter-gatherers became farmers, and cats became a form of pest control.
Other animals show multiple points of domestication, but DNA analysis supports the theory that this was the only location that initially domesticated cats. The felines then moved with humans around the world.
Another anomaly of cat domestication is that their behavior has changed much less than other animals. “We can actually refer to cats as semi-domesticated, because if we turned them loose into the wild, they would likely still hunt vermin and be able to survive, unlike dogs and other domesticated animals,” said feline geneticist Leslie Lyons.
