Science Current Events | Science News | Brightsurf.com
 
Email a Friend Send to a friend
Printer Friendly Print Missing link shows bats flew first, developed echolocation later

Missing link shows bats flew first, developed echolocation later

February 14, 2008

ANN ARBOR, Mich.---The discovery of a remarkably well-preserved fossil representing the most primitive bat species known to date demonstrates that the animals evolved the ability to fly before they could echolocate.

The new species, named Onychonycteris finneyi, was unearthed in 2003 in southwestern Wyoming and is described in a study in the Feb. 14 issue of the journal Nature, on which University of Michigan paleontologist Gregg Gunnell is a coauthor along with researchers from the American Museum of Natural History (AMNH) in New York, the Royal Ontario Museum in Canada and the Senckenberg Research Institute in Germany. A cast of one of the two known specimens is on permanent display in the U-M Exhibit Museum of Natural History's Hall of Evolution.




"There has been a longstanding debate about how bats evolved, centering around the development of flight and the development of the sonar system they use to navigate and hunt for prey," said Gunnell, an associate research scientist at the U-M Museum of Paleontology. "The three main theories have been that they developed the two abilities together, that flight came first, or that sonar came first. Based on the specimen described in this paper, we were able to determine that this particular animal was not capable of echolocating, which then suggests that bats flew before they developed their echolocation ability."

Bats represent one of the largest and most diverse orders of mammals, accounting for one-fifth of all living mammal species. The well-preserved condition of the new fossil permitted the scientists to take an unprecedented look at the most primitive known member of the order Chiroptera.

"When we first saw it, we knew it was special," said lead author Nancy Simmons of AMNH. "It's clearly a bat, but unlike any previously known. In many respects it is a missing link between bats and their non-flying ancestors."

Dating the rock formation in which the fossil was found put its age at 52 million years. Onychonycteris was not the only bat alive at the time---fossils of Icaronycteris, a more modern bat that could echolocate, are found in the same formations.

A careful examination of Onychonycteris's physical characteristics revealed several surprising features. For example, it had claws on all five of its fingers, whereas modern bats have, at most, claws on only two digits of each hand. The limb proportions of Onychonycteris are also different from all other bats---the hind legs are longer and the forearm shorter---and more similar to those of climbing mammals that hang under branches, such as sloths and gibbons.

The fossil's limb form and the appearance of claws on all the fingers suggest that Onychonycteris may have been a skilled climber. However, long fingers, a keeled breastbone and other features indicate that Onychonycteris could fly under its own power like modern bats. It had short, broad wings, which suggest that it probably could not fly as far or as fast as most bats that came after it. Instead of flapping its wings continuously while flying it may have alternated flapping and gliding while in the air. Onychonycteris's teeth indicate that its diet consisted primarily of insects, just like that of most living bats.

"We don't know what the initial incentive was to take to the air," Gunnell said. "My thought is that these bats probably were commuters at first---developing the ability to fly allowed them to travel to a particular place to feed, then fly back to their nesting area." Eventually, selective pressures likely favored the development of more sustained and agile flight, allowing bats to hunt on the wing.

Despite Onychonycteris's resemblance to animals that came after it, its skull lacks features in and around the ear seen in bats that use echolocation to navigate and hunt. The structure of its feet and ankles, which include a special, spur-like bone that likely supported a tail membrane, led the researchers to conclude that Onychonycteris had the broad tail that modern bats use to capture prey in flight, but that the structure probably was used as an airfoil to aid maneuvering. Without echolocation, Onychonycteris likely had to make do with visual, olfactory, or passive audio cues to hunt.

"It finally gives us an answer," Simmons said. "Flying evolved first, echolocation second."

University of Michigan



Related Echolocation Current Events and Echolocation News Articles Echolocation Current Events and Echolocation News RSS Echolocation Current Events and Echolocation News RSS
Spanish scientists develop echo-location in humans
A team of researchers from the University of Alcalá de Henares (UAH) has shown scientifically that human beings can develop echolocation, the system of acoustic signals used by dolphins and bats to explore their surroundings.

Bats recognize the individual voices of other bats
Bats can use the characteristics of other bats' voices to recognize each other, according to a study by researchers from the University of Tuebingen, Germany and the University of Applied Sciences in Konstanz, Germany.

Whispering bats are 100 times louder than previously thought
Annemarie Surlykke from the University of Southern Denmark is fascinated by echolocation. She really wants to know how it works. Surlykke equates the ultrasound cries that bats use for echolocation with the beam of light from a torch: you won't see much with the light from a small bulb but you could see several hundred metres with a powerful beam.

Molecular evolution is echoed in bat ears
Bats' ability to echolocate may have evolved more than once, according to research published this week by Queen Mary, University of London scientists.

Why wind turbines can mean death for bats
Power-generating wind turbines have long been recognized as a potentially life-threatening hazard for birds. But at most wind facilities, bats actually die in much greater numbers.

Slow-motion video study shows shrews are highly sophisticated predators
Shrews are tiny mammals that have been widely characterized as simple and primitive. This traditional view is challenged by a new study of the hunting methods of an aquatic member of the species, the water shrew. It reveals remarkably sophisticated methods for detecting prey that allow it to catch small fish and aquatic insects as readily in the dark as in daylight.

Bats add their voice to the FOXP2 story
When it comes to the FOXP2 gene, humans have had most to shout about. Discoveries that mutations in this gene lead to speech defects and that the gene underwent changes around the time language evolved both implicate FOXP2 in the evolution of human language.

Migrating squid drove evolution of sonar in whales and dolphins, researchers argue
Behind the sailor's lore of fearsome battles between sperm whale and giant squid lies a deep question of evolution: How did these leviathans develop the underwater sonar needed to chase and catch squid in the inky depths"

Bats prey on nocturnally migrating songbirds
It was until now believed that nocturnally migrating songbirds, while venturing into the unfamiliar night sky for accomplishing their long, challenging trans-continental migrations, could at least release anti-predator vigilance thanks to the concealment of darkness.

Beaked Whales Perform Extreme Dives to Hunt Deepwater Prey
A study of ten beaked whales of two poorly understood species shows their foraging dives are deeper and longer than those reported for any other air-breathing species.
More Echolocation Current Events and Echolocation News Articles
echolocation

echolocation
fruit bats (Performer)

Echolocation is the debut album from Fruit Bats. Imaginary pop hits about the unsettling nature of the great outdoors, murderous fireflies and vengeful pigeons. Imagine Eno and Elton John wrecking a campfire sing-along. Timeless sounds finding the calm in absurdity. Echolocation creates a world where gentle harmonies and subtle guitars frame lines like "arms ripped off by shooting stars". Mandolin and marimbas lead into a chorus where “ The light refracts through the glass in your feet". Dirty country fiddles bend into synthesizer lines and icebergs into garlic fields. Where perfect falsetto pop mixes with images of urban writer’s block and Vikings high on mushrooms all in the same song. It’s sexual, space age country music about seeing the beauty in natural disaster. It makes...

Echolocation in Bats and Dolphins

Echolocation in Bats and Dolphins
by Jeanette A. Thomas (Editor), Cynthia F. Moss (Editor), Marianne Vater (Editor)

Although bats and dolphins live in very different environments, are vastly different in size, and hunt different kinds of prey, both groups have evolved similar sonar systems, known as echolocation, to locate food and navigate the skies and seas. While much research has been conducted over the past thirty years on echolocation in bats and dolphins, this volume is the first to compare what is known about echolocation in each group, to point out what information is missing, and to identify future areas of research.

Echolocation in Bats and Dolphins consists of six sections: mechanisms of echolocation signal production; the anatomy and physiology of signal reception and interpretation; performance and cognition; ecological and evolutionary aspects of echolocation mammals; theoretical...

Echolocation

Echolocation
Public Record (Primary Contributor)



EchoLocations

EchoLocations
by Diane Thiel (Author)

At home with traditional forms and free verse patterns, Diane Thiel composes highly charged, evocative poems that celebrate and elucidate voyaging-in our own hearts and minds, to other lands, back and forth in time-the natural world, science, and her family's German heritage.

Diane Thiel's poetry has appeared in The Best American Poetry 1999, The Hudson Review, Poetry, among others. She is the author of two chapbooks, Cleft in the Wall and The Minefield, both out from Aralia Press. She has an MFA from Brown University, and she teaches at the University of Miami.

ABC News Specials Medical Mysteries Series-Episode #3

ABC News Specials Medical Mysteries Series-Episode #3

Medical science has progressed exponentially in recent times, but scientists are still left with unanswered questions when it comes to the human body. "Medical Mysteries" looks at some of the rarest disorders and syndromes in medicine today. Meet a woman whose body exudes a strange and overwhelming smell that has resulted in constant embarrassment, leaving a job, and being ridiculed for years. Next, meet a boy who is blind, but that hasn't stopped him from "seeing." He rollerblades, rides his bike, even shoots hoops. He is one of the few known people who,like a bat or a dolphin, use echolocation to "see" by the sounds he makes. Next, learn about Foreign Accent Syndrome, where a person finds themselves speaking their native language but with a distinctly different accent, and they...

Echolocation

Echolocation
by Public Record

Public Record's second release finds the band in full-on collaboration
mode as they join forces with 11 artists of differing musical backgrounds to remix and rethink five songs from the band's 2008 self-titled debut album. Echolocation boasts an original mixture of artists that should surprise those listeners expecting a typical brand of remix album. Individuals like Guy Picciottto (Fugazi, Rites of Spring), Alasdair MacLean (The Clientele), Mac McCaughan (Superchunk, Portastatic), and Quentin Stoltzfus (Mazarin) are here, remixing for the first time alongside famed indie rock producer/remixer Mark Robinson
(Unrest, Air Miami). Also featured are remixes by some promising new and underground acts like A Sunny Day In Glasgow, Collette Columbirch, and Arc In Round. The inclusion of...

Echolocation

Echolocation
by Angela Andrews (Author)

Daily rhythms and family tales dominate this quietly impressive book of poems, which examines domestic life in order to reconfirm its virtues. Though the subject matter is uncompromisingly orthodox, with ruminations on having a baby in the home and another on the way, the writing uses undeniable grace and exactness to cut to the heart of what truly matters in life.



Heavy Ornament (Portastatic "Heavy Thumbs" Remix)

Heavy Ornament (Portastatic "Heavy Thumbs" Remix)
Public Record (Primary Contributor)



  Echolocation
by Baze



  Echolocation in animals
by E. Sh Airapetiants (Author)



© 2009 BrightSurf.com