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The complex social system known as eusociality is marked by cooperative care of young, overlapping generations, and distinct castes, like workers and breeders. It is found in a variety of organisms such as shrimp, social insects like bees and ants, and mole-rats. Eusociality is a case of kin selection, in which individuals find that helping a relative may provide more overall fitness for themselves than being selfish. In a eusocial society, workers relinquish most, if not all, of their breeding rights to help raise another’s offspring, usually closely related to them, thereby gaining indirect fitness. The mole-rat is an excellent example of how eusociality evolves, as not all species of mole-rats are eusocial. This evolution is best explained by the Aridity Food Distribution Hypothesis which accounts for the environmental constrictions of predators and scarce resources that make helping close kin more beneficial for one’s own genes than risking death in the harsh conditions. Evolution of eusociality has developed distinct tiers of breeders, workers, and dispersers who are essential for reproducing, foraging, and maintaining some genetic drift. The mechanisms behind how these tiers are maintained are not entirely understood, but appear to be a combination of physical factors such as verterbrate length and hormone suppression of reproductive behavior in non-breeder tiers.

Author: Sheena Shah-Simpson

Introduction

Mole-rats (family Bathyergidae) are a type of rodent found in Africa. They live underground in burrows made up of different chambers for their nests, latrines, food storage areas, alongside chambers for foraging, in which they dig with their incisors and foreclaws. They eat roots, tubers, and bulbs. Most species of mole-rat are solitary, coming together only for mating. A few species, though, form colonies where many mole-rats live together in large complex burrows they have dug because it makes it easier to gather food and reduces predation risks.

Of the species that live in colonies, eusociality has evolved independently at least twice, in Heterocephalus glaber , the naked mole-rat ( [link] ), and separately in Cryptomys damarensis , the Damaraland mole-rat (Allard and Honeycutt 1992, Jarvis and Bennett 1993, Walton et al. 2000, Faulkes et al. 2004). Colonies in both species have three morphologically distinct castes. The first caste is made up of the breeders, usually one female “queen” and her one to three mates, who breed and encourage the workers in their daily tasks. The second caste is formed by the workers, usually mole-rats who are highly related to the queen. These workers are reproductively suppressed by their own hormones that are secreted due to social cues from the queen, keeping them working instead of reproducing. They take care of the offspring, forage for food, and patrol the burrows. The final caste is the dispersal caste, made up of mole-rats of a slightly larger build who act as workers until they leave the colony to either found or join another. The dispersal caste is virtually the only form of gene flow in these mole-rat populations since the colonies are usually separated by a large distance that is dangerous for mole-rats to cross above ground.

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
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Source:  OpenStax, Mockingbird tales: readings in animal behavior. OpenStax CNX. Jan 12, 2011 Download for free at http://cnx.org/content/col11211/1.5
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