A passion for the natural world drives many of our adventures. And when we’re not actually outside, we love delving into the discoveries about the places where we live and travel. Here are some of the best natural history links we’ve found this week.
Geologists dig into Grand Canyon’s mysterious time gap: Over one billion years worth of rocks are missing from the Grand Canyon’s geological record. This “Great Unconformity” has confused geologists for 150 years. New research suggests a series of small and violent faulting events hit the region during the break up of Rodinia, an ancient super-continent. The events caused rocks and sediment to wash into the sea, where they vanished from the geological timeline.
An ancient green corridor in Arabia
Stone Age humans trekked through a green Arabia: Four hundred thousand years ago, Arabia acted as a “green turnstile” for Stone Age humans. Monsoon rains meant that northern Arabia could serve as a passageway out of Africa for early humanity. Analysis of five ancient lake beds in the area showed stone tools, sediment from a wetter climate, and fossils of hippos, wild cattle, and other animals. The various animals migrated into the now-desert landscape for its lakes, wetlands, and rivers.
Three new species of skunk: DNA analysis of over 200 animals has found seven distinct species of spotted skunk. This is three more than previously thought. “[To be] able to redraw the skunk family tree is very exciting,” said Dr. Adam Ferguson. The analysis showed that the Plains spotted skunk, previously denoted as a subspecies, is a separate species. Its identification is good news for the mammal. “If a subspecies is in trouble, there’s sometimes less emphasis on protecting it because it’s not as distinct an evolutionary lineage as a species,” said Ferguson.
The Eastern Spotted Skunk. Photo: Shutterstock
Fires penetrate deeper into the rainforest
Fires may have affected 85% of threatened Amazon species: For two decades, forest fires have ravaged the Amazon rainforest. They have destroyed thousands of plant and animal species. These fires have affected 85% of threatened species in the region. “If the fire-impacted area continues to rise, not only does the Amazon lose forest cover, but also some of its capacity to cope with the changing climate,” said ecologist Arie Steel. As fires occur deeper into the rainforest, more species experience fire for the first time. As they have not evolved in these conditions, population decline and extinction are likely.
Galapagos pink land Iguana on verge of extinction: The Galapagos pink land iguana is critically endangered. First identified in 1986, it is distinct from the Galapagos land iguana. In a 10-day expedition across Wolf Volcano, the pink iguanas’ only habitat, researchers counted just 211 iguanas. Worryingly, none of them were juveniles, causing concern for the future of the species.
The third shark
“Virgin birth” of shark in Italy: Two female smoothhound sharks have lived in the shark tank at Cala Gonone Aquarium in Sardinia, Italy for 10 years. In August, staff discovered a third, newborn shark in the tank. The new addition is the result of a rare “virgin birth”. The phenomenon is parthenogenesis: When a female fertilizes her own egg. It occurs in some sharks and rays before but never before in this species. “It is difficult to detect in the wild, so we really only know about it from captive animals,” said Demian Chapman from the Mote Marine Laboratory and Aquarium in Florida.
African wild dogs. Photo: Shutterstock
African wild dogs use diverse cover to survive around lions: African wild dogs are one of the top predators in sub-Saharan Africa. The only animal that they won’t challenge is a lion. Lions view the dogs as a threat to their food source. To avoid this alpha predator, the dogs are experts at hiding. They use the scrub brush, holes, gullies, and brambles to camouflage from the lions.
