Featured Research

from universities, journals, and other organizations

Evolutionary Shifts In Olfactory Sensitivities In Fruit Flies

Date:
January 19, 2006
Source:
Cell Press
Summary:
How do an animal's senses change as it evolves to occupy a new ecological niche? By comparing the olfactory system of the fruit fly Drosophila melanogaster, which feeds from multiple fruit types, with that of its sibling species D. sechellia, a specialist particularly drawn to a single fruit type, researchers have demonstrated how evolution can act on several different levels of a sensory system to create a supersensitive detection system for a specific food source and egg-laying environment.

How do an animal's senses change as it evolves to occupy a new ecological niche? By comparing the olfactory system of the fruit fly Drosophila melanogaster, which feeds from multiple fruit types, with that of its sibling species D. sechellia, a specialist particularly drawn to a single fruit type, researchers have demonstrated how evolution can act on several different levels of a sensory system to create a supersensitive detection system for a specific food source and egg-laying environment.

Related Articles


The findings are reported by researchers Teun Dekker, Irene Ibba, Purayil Siju, Marcus Stensmyr, and Bill S. Hansson of the Swedish University of Agricultural Sciences.

Most insects rely on their olfactory system to detect mates, food, and egg-laying sites. This also holds true for fruit flies in the genera Drosophila. Both the peripheral and the central olfactory systems have been mapped in detail in D. melanogaster, an important model organism for research. However, nine sibling species of D. melanogaster are less well characterized. One of these species, D. sechellia--as its name suggests, it is endemic to the Seychelles islands--relies exclusively on one fruit, called the morinda fruit, for egg-laying. This fruit, which smells of gorgonzola and pineapple, is toxic to, and shunned by, D. melanogaster and other sibling fruit fly species.

In their new work, the researchers show that the main cue used by D. sechellia when locating morinda fruit is methyl hexanoate (MeHex), which possesses a pineapple-like odor. The researchers found that olfactory hairs (sensilla) on the antenna that house receptor neurons specific to the MeHex odor have become three times more numerous, and one hundred times more sensitive, in D. sechellia than in the sibling species D. melanogaster. In parallel, a specific brain area (a so-called olfactory glomerulus) that receives input from the MeHex-specific neurons is significantly increased in size in D. sechellia. The researchers' findings indicate that the relative overexpression of MeHex-specific receptor neurons in D. sechellia compared to D. melanogaster has occurred at the expense of two other types of sensilla.

The work suggests that the evolution of a specialized olfactory system can occur during a limited evolutionary time span, and at several different levels of neural organization. More broadly speaking, the findings contribute to our understanding of the evolution of sensory systems and their adaptation to new conditions and resources.

###

The researchers include Teun Dekker, Irene Ibba, K.P. Siju, Marcus C. Stensmyr, and Bill S. Hansson of the Swedish University of Agricultural Sciences in Alnarp, Sweden. This work was supported by an EU Marie Curie fellowship to T.D. and by a Swedish Research Council (VR) grant to B.S.H.

Dekker et al.: "Olfactory Shifts Parallel Superspecialism for Toxic Fruit in Drosophila melanogaster Sibling, D. sechellia." Publishing in Current Biology Vol. 16, Issue 1, pages 101-109, January 10, 2006. DOI 10.1016/j.cub.2005.10.075, www.current-biology.com


Story Source:

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


Cite This Page:

Cell Press. "Evolutionary Shifts In Olfactory Sensitivities In Fruit Flies." ScienceDaily. ScienceDaily, 19 January 2006. <www.sciencedaily.com/releases/2006/01/060118100200.htm>.
Cell Press. (2006, January 19). Evolutionary Shifts In Olfactory Sensitivities In Fruit Flies. ScienceDaily. Retrieved April 1, 2015 from www.sciencedaily.com/releases/2006/01/060118100200.htm
Cell Press. "Evolutionary Shifts In Olfactory Sensitivities In Fruit Flies." ScienceDaily. www.sciencedaily.com/releases/2006/01/060118100200.htm (accessed April 1, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Wednesday, April 1, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Gorilla Falls Into Zoo Moat

Gorilla Falls Into Zoo Moat

Reuters - Light News Video Online (Mar. 31, 2015) A gorilla comes to the rescue of her sister who fell into a moat in Israel&apos;s Safari zoo. Rough cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
California on Alert Over Surge in Sea Lion Strandings

California on Alert Over Surge in Sea Lion Strandings

AFP (Mar. 31, 2015) Since the start of the year, thousands of baby sea lions have washed up on beaches along the west coast of the United States. Marine animal care centers are working around the clock to save the stranded creatures. Duration: 02:06 Video provided by AFP
Powered by NewsLook.com
Giant Amphibian Fossils Found in Portugal

Giant Amphibian Fossils Found in Portugal

Reuters - Light News Video Online (Mar. 31, 2015) Scientists discover a new species of giant amphibian that was one of the largest predators on earth about 220 million year ago. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Rhino Goes on Deadly Rampage in Nepal

Rhino Goes on Deadly Rampage in Nepal

Reuters - News Video Online (Mar. 31, 2015) A rhino runs rampant down a bustling city street, killing one woman and injuring several others, before security personnel chase it back into the forest. Vanessa Johnston reports. 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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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