In one of the tallest trees on earth, a brown, drawn salamander rises above a fern that grows up its trunk. When it reaches the shore, the amphibian jumps like a parachutist leaving the plane.
The salamander’s confidence seems to have been well earned. Brave amphibians can skillfully control their descent, planning to maintain the broad posture of a parachutist, the researchers reported on May 23rd. Current Biology.
Walking Salamanders (Aneides vagrans) They are native to a forest list in northwestern California. They climb to the fat of traditional coastal redwoods (Sequoia sempervirens). There, up to 88 meters high, amphibians live in fern mats that grow in a miniature hanging ecosystem. Unlike many salamanders who spend the day in streams or peat bogs, some of these walkers can spend their entire lives in the trees.
These integrative biologist Christian Brown was studying these explorers at the State Polytechnic University of California, Humboldt, as a graduate student at Arcata, when he noticed that they would jump from a hand or branch when they were disturbed.
At the University of South Florida in Tampa, Brown and his colleagues were asked if the salamander tree patterns and jumping tendencies were related, and whether small creatures could be oriented in a fall.
Brown and his team captured five A. vagransslightly less tree species (A. lugubris), and two terrestrial salamanders (A. flavipunctatus and Ensatina eschscholtzii). The researchers then placed each salamander in a vertical wind tunnel to simulate falling from a tree, recording the animal’s movements with a high-speed camera.
In all 45 trials, the drifting salamanders showed strict control, using their extended limbs and tail to maintain a stable position in the air and constantly adjusting to navigation. All of these salamanders slowed the rate of fall, which researchers call parachuting, once using their attachments, and many changed course and moved horizontally, or slid.
“It simply came to our notice then [the salamanders] they could be kept upright. However, we never expected parachuting or planning to be observed, ”says Brown. “They were able to slow down and change direction.”
A. lugubris he had similar air dexterity A. vagrans but slipped less (36 percent versus 58 percent). The two embraces on the ground were mostly shaken ineffectively by the wind.
The maneuverable slip of the walking salamander is probably of great value at the peaks of the redwoods, Brown says. Aerating a fern mat or branch in an unexpected fall would save you the effort of crawling into a tree. Planning to jump from an hungry owl or a carnivorous mammal can also be a viable option.
Brown suspects that salamanders can also use planning to access better patches for life. “Maybe your fern matrix is drying up, maybe there are no bugs. There may not be a partner in your fern matrix, you look down; there’s another fern match, ”says Brown. “It simply came to our notice then [risk] when you are caught, can you take the gravity lift?
There are other tree salamanders in the tropics, but these are not nearly as tall A. vagranssays Erica Baken, a macro-evolutionary biologist at Chatham University in Pittsburgh who did not participate in the research.
“It would be interesting to know if there is a height [gliding] it evolves, ”he says.
A. vagransA fairly flat body, long legs and large feet can give you more control in the air. Brown and his colleagues are using computer simulations to test how it can affect the planning of body proportions.
If the body adjustments were significant, they would not be as noticeable as the widespread, elongated shapes seen in other animals, such as flying snakes and snakes, which are known to slip (SN: 20/6/29; SN: 20/11/20). Brown says there may be many animals that live in trees that have conventional body plans that have been forgotten as gliders. “The panel world has begun to expand.”