Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Disparate Mole-rats: Underground Soap Opera Brings New Science to Light

12.08.2005


This is all underground, and naked mole-rats prefer it that way: Momma naked mole-rat is the only one having babies, and she’s got several naked mole-rat boyfriends.

Were it human, the family would argue it out on a national talk show. As it is, the social behavior of these tiny rodents has scientists intrigued, right down to their naked mole-rat molecules.

"African mole-rats are very good models for studying social structure. I’m interested in the genetic markers associated with structure," said Colleen Ingram, whose doctoral degree will be bestowed Friday at Texas A&M University based on her findings about the critters’ parentage.



Ingram looked at regions of DNA - specifically the microsatellites, which represent distinct DNA bands, much like a satellite, which separate from the main DNA band. These rapidly changing regions of DNA don’t code for any particular trait, as far as scientists can tell. Ingram thought these regions shouldn’t be overlooked.

"If there is a random-mating population, there are a lot of sizes of those DNA bands, but a child only gets one set from the mother and one from the father," Ingram noted. These markers are used in paternity cases for humans, she said.

She looked for changes in the processes and patterns of this strand in mole-rats, she said.

"The current methods of analyses of microsatellite markers are oversimplified and may lead to incorrect conclusions when looking at natural populations and their social structures," Ingram said. "The relationship among members of the mole-rat family are well-accepted. Some species (of mole-rat) are strictly solitary while others, such as the naked mole-rat, are highly social."

DNA markers, like the satellites, are important because they can reveal how traits pass from one mother to her multitude of babies conceived by various interrelated fathers. That may help understand why scores of offspring in the family are willing to support the mother naked mole-rat.

But first, naked mole-rats. They live in Somalia, Ethiopia and Kenya. They are 3-6 inches long, have pink furless skin, tiny eyes which never see the light of day, and long front teeth for digging. Despite their tiny size, the naked mole-rat family den may stretch for 2 miles entirely underground, with various rooms. In one room, a plant root protrudes to provide a meal; in another is the "potty." When a new hallway is needed, usually for new food supplies, the naked mole-rat siblings form an earth moving chain to pass dirt out a hole which later is covered to block out intruders.

The most unusual room is the largest. It’s where Momma naked mole-rat produces more babies – as many as 12 at a time every couple of months. Here she is stoked by her numerous mates and tended to by any number of offspring whose lot in life - if not to dig tunnels - is to keep Momma happy.

This behavior is common – even accepted and marveled over – in insects such as bees, termites and ants. But the naked mole-rat, a mammal, is the most advanced species to live in this arrangement, said Dr. Rodney Honeycutt, Texas A&M Univeristy wildlife professor whose 1992 article in American Scientist explained naked mole-rat life.

Scientists call it "eusocial" in that the young are cared for by the group, individuals in the group give up their ability to reproduce in order to do other jobs, and there are at least two generations that overlap to do the family’s work, Honeycutt noted.

Why don’t teenaged naked mole-rats revolt and head for their own tunnel? That’s where genetics may play a role.

"Biological evolution is generally seen as a competition, a contest among individuals struggling to survive and reproduce," said Honeycutt, who was Ingram’s lead professor and began studying mole-rats in the early 1980s while at Harvard

"It runs counter to everything we know about evolution," Honeycutt said. "In fact, (Charles) Darwin himself said social animals represent a real challenge to his theory (of natural selection and individual fitness)."

Honeycutt explained that after several generations of inbreeding, the offspring – say two sisters – may be more closely related to each other than to the parents. They preserve themselves by helping mother produce more offspring with their genetic makeup.

Knowing why animals exist with or without social structures could be more far reaching than the intricate underground tunnels of the naked mole-rat. What scientists learn about its genetic connection to social behavior could ultimately impact how endangered species, for example, are managed for survival, Ingram said. The fewer the animals of one species, the smaller its gene pool.

Ingram will continue her work with conservation genetics in her new position at the American Museum of Natural History in New York.

Kathleen Phillips | EurekAlert!
Further information:
http://agnews.tamu.edu/dailynews/stories/WFSC/photos/Aug1005a.htm
http://www.tamu.edu

More articles from Life Sciences:

nachricht Mass spectrometry sheds new light on thallium poisoning cold case
14.12.2018 | University of Maryland

nachricht Protein involved in nematode stress response identified
14.12.2018 | University of Illinois College of Agricultural, Consumer and Environmental Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>