Featured Research

from universities, journals, and other organizations

Morphing bat skull model: Using engineering plus evolutionary analyses to answer natural selection questions

Date:
January 23, 2014
Source:
University of Massachusetts at Amherst
Summary:
Scientists have built an engineering model of a bat skull that can morph into the shape of any species, and used it to create skulls with all possible combinations of snout length and width. Then they ran engineering analyses on all the models to assess their structural strength and mechanical advantage, a measure of how efficiently and how hard bats can bite.

Glossophaga soricina, a nectarivorous bat, feeding on the flowers of a banana plant. Nectar feeding bats comprised one of three evolutionary optima for mechanical advantage among New World Leaf-nosed bats.
Credit: Beth Clare, Queen Mary University of London

Introducing a new approach that combines evolutionary and engineering analyses to identify the targets of natural selection, researchers report in the current issue of Evolution that the new tool opens a way of discovering evidence for selection for biomechanical function in very diverse organisms and of reconstructing skull shapes in long-extinct ancestral species.

Evolutionary biologist Elizabeth Dumont and mechanical engineer Ian Grosse at the University of Massachusetts Amherst, with evolutionary biologist Liliana Dαvalos of Stony Brook University and support from the National Science Foundation, studied the evolutionary histories of the adaptive radiation of New World leaf-nosed bats based on their dietary niches.

As the authors point out, adaptive radiations, that is, the explosive evolution of species into new ecological niches, have generated much of the biological diversity seen in the world today. "Natural selection is the driving force behind adaptation to new niches, but it can be difficult to identify which features are the targets of selection. This is especially the case when selection was important in the distant past of a group whose living members now occupy very different niches," they note.

They set out to tackle this by examining almost 200 species of New World leaf-nosed bats that exploit many different food niches: Insects, frogs, lizards, fruit, nectar and even blood. The bats' skulls of today reflect this dietary diversity. Species with long, narrow snouts eat nectar, while short-faced bats have exceptionally short, wide palates for eating hard fruits. Species that eat other foods have snouts shaped somewhere in between.

Dumont explains further, "We knew diet was associated with those things, but there was no evidence that natural selection acted to make those changes in the skull. The engineering model allowed us to identify the biomechanical functions that natural selection worked on. Some form or function helps an animal to perform better in its environment, but it can be hard to demonstrate exactly what that form or function is. We studied the engineering results using the evolutionary tree, which is a very cool new thing about this work."

She and colleagues built an engineering model of a bat skull that can morph into the shape of any species, and used it to create skulls with all possible combinations of snout length and width. Then they ran engineering analyses on all the models to assess their structural strength and mechanical advantage, a measure of how efficiently and how hard bats can bite.

Analyzing the engineering results over hundreds of evolutionary trees of New World leaf-nosed bats revealed three optimal snout shapes favored by natural selection, they report. One was the long, narrow snout of nectar feeders, the second was the extremely short and wide snout of short-faced bats, and the third optimum included all other species. Overall, selection for mechanical advantage was more important in determining the optima than was selection for structural strength, they add.

"Thanks to this new approach," Dumont says, "we were able to answer our original question about natural selection in the evolution of these bats. It favored the highest mechanical advantage in short-faced bats, which gives them the high bite forces needed to pierce through the hardest figs. Nectar feeders have very low mechanical advantage, which is a trade-off for having long, narrow snouts that fit into the flowers in which they find nectar."


Story Source:

The above story is based on materials provided by University of Massachusetts at Amherst. Note: Materials may be edited for content and length.


Journal Reference:

  1. Elizabeth R. Dumont, Krishna Samadevam, Ian Grosse, Omar M. Warsi, Brandon Baird, Liliana M. Davalos. SELECTION FOR MECHANICAL ADVANTAGE UNDERLIES MULTIPLE CRANIAL OPTIMA IN NEW WORLD LEAF-NOSED BATS. Evolution, 2014; DOI: 10.1111/evo.12358

Cite This Page:

University of Massachusetts at Amherst. "Morphing bat skull model: Using engineering plus evolutionary analyses to answer natural selection questions." ScienceDaily. ScienceDaily, 23 January 2014. <www.sciencedaily.com/releases/2014/01/140123133219.htm>.
University of Massachusetts at Amherst. (2014, January 23). Morphing bat skull model: Using engineering plus evolutionary analyses to answer natural selection questions. ScienceDaily. Retrieved April 24, 2014 from www.sciencedaily.com/releases/2014/01/140123133219.htm
University of Massachusetts at Amherst. "Morphing bat skull model: Using engineering plus evolutionary analyses to answer natural selection questions." ScienceDaily. www.sciencedaily.com/releases/2014/01/140123133219.htm (accessed April 24, 2014).

Share This



More Fossils & Ruins News

Thursday, April 24, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

New Pictures of Ship That Sank in 1888

New Pictures of Ship That Sank in 1888

AP (Apr. 24, 2014) — Federal researchers have released new images of the City of Chester, a steamship that sank in San Francisco Bay in 1888. Researchers recently found the shipwreck while mapping shipping routes. (April 24) Video provided by AP
Powered by NewsLook.com
Mich. Boy Unearths 10,000-Year-Old Mastodon Tooth

Mich. Boy Unearths 10,000-Year-Old Mastodon Tooth

Newsy (Apr. 20, 2014) — A 9-year-old Michigan boy was exploring a creek when he came across a 10,000-year-old tooth from a prehistoric mastodon. Video provided by Newsy
Powered by NewsLook.com
Couple Finds Love Letters From WWI In Attic

Couple Finds Love Letters From WWI In Attic

Newsy (Apr. 17, 2014) — A couple found love letters from World War I in their attic. They were able to deliver them to relatives of the writer of those letters. Video provided by Newsy
Powered by NewsLook.com
Erotic Art Offers Glimpse of China's 'lost' Sexual Philosophy

Erotic Art Offers Glimpse of China's 'lost' Sexual Philosophy

AFP (Apr. 16, 2014) — Explicit Chinese art works dating back centuries go on display in Hong Kong, revealing China's ancient relationship with sex. Video provided by AFP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins