Featured Research

from universities, journals, and other organizations

Bats evolved more than one way to drink nectar

Date:
August 17, 2012
Source:
Stony Brook University
Summary:
A team of evolutionary biologists compared the anatomy and genes of bats to help solve a persistent question in evolution: Why do analyses of different features of an organism result in conflicting patterns of evolutionary relationships?

Two nectar-feeding bats in the Neotropical family Phyllostomidae; the glossophagine Pallas's long-tongued bat, Glossophaga soricina, (left) and the lonchophylline orange nectar bat, Lonchophylla robusta, (right). In a new study Dávalos, Cirranello, et al., show that many anatomical features implying a common origin of nectar feeding for glossophagines and lonchophyllines — such as a long, extensible tongue — are related to their shared diet. Their evolutionary patterns are consistent with natural selection.
Credit: Felineora (left), Marco Tschapka (right).

A team of evolutionary biologists compared the anatomy and genes of bats to help solve a persistent question in evolution: Why do analyses of different features of an organism result in conflicting patterns of evolutionary relationships? Their findings, "Understanding phylogenetic incongruence: lessons from phyllostomid bats," appear in the August 14 edition of Biological Reviews.

To answer this question, Liliana Dávalos, PhD, Assistant Professor in the Department of Ecology and Evolution, and member of the Consortium for Inter-Disciplinary Environmental Research (CIDER) at Stony Brook University, and Andrea Cirranello of the Division of Vertebrate Zoology at the American Museum of Natural History (AMNH), together with colleagues at the AMNH and the New York College of Osteopathic Medicine, examined the skin, skeleton, muscle, tongue, internal organs and a few genes of a family of New World bats, applying statistical models to uncover the genetic and anatomical features that produced the conflicts between evolutionary patterns. This work was funded in part by the National Science Foundation.

Specifically, the team examined why genes suggested that nectar feeding had evolved twice in Leaf-Nosed bats, while the anatomical features strongly pointed to a single origin of nectar feeding in this group. Most bats feed on insects, but New World Leaf-Nosed bats are exceptionally diverse in that they feed on nectar, fruit, frogs, lizards and even blood.

One hypothesis that the team tested is that traits linked to how bats feed have been shaped by natural selection for a nectar-based diet, resulting in the conflicting pattern. As Dávalos and Cirranello explain, connecting the conflicting pattern to the diet requires showing that the evolutionary pattern resulting from anatomical traits is wrong, and that the traits producing the conflict with the genetic data are linked to a shared dietary specialization.

"If a diet specializing in nectar helped shape the anatomy of the two groups of bats, then the traits that support the groups coming together should be related to feeding, and taking those traits out should break up the spurious group of nectar-feeding bats," the researchers said. They found support for these predictions by analyzing evolutionary trees from two genomic data sets, alongside trees based on more than 200 anatomical traits; and applying a battery of statistical approaches to identify where in the evolutionary tree the conflicts arose and what genetic regions and traits supported the differences.

The team traced the conflict in evolutionary patterns among nectar-feeding bats to traits linked to feeding, such as the shape and number of teeth, gaining a "paintbrush" type tongue tip, and rearranging the tongue muscles to accommodate longer, extensible tongues. All of these traits are thought to be associated with specialized nectar feeding. The grouping of all nectar-feeding bats broke down into smaller groups when those traits were taken out of the analyses. Overall, the team found that anatomical traits and the studied genes tended to agree on many parts of the evolutionary tree, but that the anatomical traits associated with nectar feeding brought nectar-feeding bats together.

Natural selection has shaped the anatomy of organisms, but when specializations evolved long ago, it can be difficult for evolutionary biologists to demonstrate that traits bear its signature. By ruling out other biological processes that produce conflict among evolutionary trees, and tracing the conflict to specific traits that are known to enable drinking nectar, the team was able to narrow the options and discover patterns consistent with the signature of adaptation to diet. "We found that anatomical traits associated with nectar feeding have evolved and been lost several times, so they tend to bring bats from different branches of the evolutionary tree together, in direct conflict with genetic trees," Dávalos and Cirranello said.


Story Source:

The above story is based on materials provided by Stony Brook University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Liliana M. Dávalos, Andrea L. Cirranello, Jonathan H. Geisler, Nancy B. Simmons. Understanding phylogenetic incongruence: lessons from phyllostomid bats. Biological Reviews, 2012; DOI: 10.1111/j.1469-185X.2012.00240.x

Cite This Page:

Stony Brook University. "Bats evolved more than one way to drink nectar." ScienceDaily. ScienceDaily, 17 August 2012. <www.sciencedaily.com/releases/2012/08/120817151501.htm>.
Stony Brook University. (2012, August 17). Bats evolved more than one way to drink nectar. ScienceDaily. Retrieved April 18, 2014 from www.sciencedaily.com/releases/2012/08/120817151501.htm
Stony Brook University. "Bats evolved more than one way to drink nectar." ScienceDaily. www.sciencedaily.com/releases/2012/08/120817151501.htm (accessed April 18, 2014).

Share This



More Plants & Animals News

Friday, April 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Vermont Goat Meat Gives Refugees Taste of Home

Vermont Goat Meat Gives Refugees Taste of Home

AP (Apr. 18, 2014) — Dairy farmers and ethnic groups in Vermont are both benefiting from a unique collaborative effort that's feeding a growing need for fresh and affordable goat meat. (April 18) Video provided by AP
Powered by NewsLook.com
First Ever 'Female Penis' Discovered In Animal Kingdom

First Ever 'Female Penis' Discovered In Animal Kingdom

Newsy (Apr. 18, 2014) — Not only are these newly discovered bugs' sex organs reversed, but they also mate for up to 70 hours. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) — A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
The Great British Farmland Boom

The Great British Farmland Boom

Reuters - Business Video Online (Apr. 17, 2014) — Britain's troubled Co-operative Group is preparing to cash in on nearly 18,000 acres of farmland in one of the biggest UK land sales in decades. As Ivor Bennett reports, the market timing couldn't be better, with farmland prices soaring over 270 percent in the last 10 years. Video provided by Reuters
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