henry astley – Shamskm: A site to exchange knowledge and solutions

Celebrated jumping frogs: For top hops, scientists look to Calaveras pros

By Guest PostOctober 21, 2013Sciencebiologist, brown university, bullfrog, calaveras county, calaveras pros, celebrated jumping frogs, frog jockeys, georgia tech university, guinness book, henry astley, jumping frog jubilee, justin bookey, muscle, rhode island, richard marsh, rosie the ribiter, technique, tendon, thomas roberts, trial and error, world records

The Calaveras County Jumping Frog Jubilee has entered the scientific record via a new paper in the Journal of Experimental Biology. Experienced bullfrog ‘jockeys’ at the event routinely get their frogs to jump much farther than researchers had ever measured in the lab. How? Decades of refined technique, uncommonly motivated humans and herps, and good old-fashioned large sample size.

PROVIDENCE, R.I. [Brown University] — One day, amid his decades-long study of how animals move, including how frogs jump, Brown University biologist Thomas Roberts found himself and colleague Richard Marsh puzzling over the Guinness Book of World Records. A bullfrog named Rosie the Ribiter reportedly had jumped more than 2.1 meters in a single hop at the Calaveras County Jumping Frog Jubilee in 1986, but scientific studies had never reported a bullfrog jump beyond 1.3 meters. (more…)

Five-Limbed Brittle Stars Move Bilaterally, Like People

By Guest PostMay 14, 2012Natureanimals, belize, bilateral symmetry, bilaterally symmetrical, brain, brittle stars, brown university, bushnell foundation, david orenstein, direction, five limbed, henry astley, humans, locomotion, mark bertness, move bilaterally, ophiocoma echinata, pentaradially symmetrical, radial symmetrical

Brittle stars and people have something in common: They move in fundamentally similar ways. Though not bilaterally symmetrical like humans and many other animals, brittle stars have come up with a mechanism to choose any of its five limbs to direct its movement on the seabed. It’s as if each arm can be the creature’s front, capable of locomotion and charting direction. Results appear in the Journal of Experimental Biology.

PROVIDENCE, R.I. [Brown University] — It appears that the brittle star, the humble, five-limbed dragnet of the seabed, moves very similarly to us.

In a series of first-time experiments, Brown University evolutionary biologist Henry Astley discovered that brittle stars, despite having no brain, move in a very coordinated fashion, choosing a central arm to chart direction and then designating other limbs to propel it along. Yet when the brittle star wants to change direction, it designates a new front, meaning that it chooses a new center arm and two other limbs to move. Brittle stars have come up with a mechanism to choose any of its five limbs to be central control, each capable of determining direction or pitching in to help it move. (more…)

Frogs’ Amazing Leaps Due to Springy Tendons

By Guest PostDecember 3, 2011Nature, Science3 d x ray video technology, biomechanics of frog jumping, brown university, bush babies, calaveras county, elastic mechanism, elastic structure, frog jumping, frog jumping competition, frogs, grasshopper, guinea fowl, henry astley, humble flea, invertebrates, milliseconds, muscles, northeast united states, northern leopard frog, pond frog, rana pipiens, richard lewis, species of frogs, thomas roberts, vertebrates

*The secret to frogs’ superlative jumping lies in their tendons. Researchers at Brown University, filming frogs jumping at 500 frames per second with special X-ray technology, show that the frog’s tendon stretches as it readies its leap and then recoils, much like a spring, when the frog jumps. The finding could explain how other animals are exceptional leapers. Results appear in Biology Letters.*

PROVIDENCE, R.I. [Brown University] — Some species of frogs and many other animals are able to jump far beyond what appear to be their capabilities. The trained contestants in the frog-jumping competition in Calaveras County, Calif., come to mind, but even ordinary frogs can leap several times farther than their physiology would seem to allow.

“Muscles alone couldn’t produce jumps that good,” said Henry Astley, who studies the biomechanics of frog jumping at Brown University. (more…)

Tag Archives: henry astley

Celebrated jumping frogs: For top hops, scientists look to Calaveras pros

Five-Limbed Brittle Stars Move Bilaterally, Like People

Frogs’ Amazing Leaps Due to Springy Tendons