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A York University doctoral student who discovered a new species of bee on his way to the lab one morning has completed a study that examines 84 species of sweat bees in Canada. Nineteen of these species -- including the one Jason Gibbs found in downtown Toronto − are new to science because they have never been identified or described before.

Gibbs' expansive study will help scientists track bee diversity, understand pollination biology and study the evolution of social behaviour in insects. It is also much anticipated by bee taxonomists who, like Gibbs, painstakingly examine the anatomy (morphology) of bees to distinguish one type of bee from another.

Bees are responsible for pollinating many wildflowers and a large proportion of agricultural crops. As much as one of every three bites of food that humans eat, including some meat products, depends on the pollination services of bees. Sweat bees are common visitors to a wide range of plants, including fruit and vegetable flowers in Toronto gardens. Sweat bees − named for their attraction to perspiration − can be smaller than 4 mm in length, often have metallic markings, and make up one-third to one-half of bees collected in biodiversity surveys in North America. Complete species descriptions of 84 metallic sweat bees in Canada are included in Gibbs' study, "Revision of the metallic species of Lasioglossum (Dialictus) in Canada." It was published August 31 by the peer-reviewed journal Zootaxa as a single issue.

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Evolutionary biologists overturn long-held kin-selection theory.

Altruistic behaviour, such as sterile worker ants caring for the offspring of their queen, evolves only between related individuals through what is known as kin selection — or so many evolutionary biologists have thought since the 1960s.

They argue that the standard theory of natural selection cannot explain the evolution of eusocial groups of organisms such as bees and ants, because the sterile workers in those groups do not themselves reproduce.

A two-part mathematical analysis, published in Nature this week, overturns this tenet by showing that it is possible for eusocial behaviour to evolve through standard natural-selection processes.

Kin selection is based on 'inclusive fitness', the idea that, for example, sterile workers can accrue reproductive benefits by helping their relatives. In doing so, they help shared genes to survive and get passed on to the next generation. This provides a route for eusociality to evolve.

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A worker Harpegnathos saltator (a jumping ant) engaged in battle with a rival colony's queen:

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Genome sequences offer clues on how to be a queen and live a long life.

Some are nomadic warriors, others the world's oldest farmers, and still others power their societies with slavery or child labour — such is the diversity of ant communities. A paper published in Science this week sheds light on the molecular forces that drive such differences.

The paper presents the genome sequences of two ant species — one (Harpegnathos saltator) with a primitive social structure, and the other, the carpenter ant (Camponotus floridanus), which has a more complex social structure.

Ants of the same species but in different social castes have the same DNA sequence but assume radically different characteristics as a result of 'epigenetic changes' — DNA modifications that affect the expression of genes rather than the genes themselves. By examining the sequences from the two ant species, the researchers were able to identify how these epigenetic changes affect the ants' characteristics.

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The coconut rhinoceros beetle continues to munch its way through the crowns of coconut trees on the northwest coast of Guam. Rhino hunters are ready to get tough with bio-control measures that will decrease the rhino beetle population.

Russ Campbell, Guam's territorial entomologist and Aubrey Moore, UOG extension entomologist, welcomed New Zealand scientist, Trevor Jackson to Guam in early June. Jackson was invited to assist in the release of a virus into the rhino beetle (Oryctes rhinoceros) population. This virus only infects rhino beetles and it has been successful in controlling populations of the pest on other Pacific islands.

The virus is naturally occurring in Malaysia and is produced in a New Zealand laboratory. It is dispersed using autodissemination: adult beetles are fed a solution of the virus, become infected, and then they are released to infect the resident population. This method of bio-control has been successfully used in Samoa, Fiji, Tonga, Palau and other Pacific islands where the rhino beetle was accidentally introduced. It will take several months to see the results. "The bio-control agent will not completely eradicate the CRB, but it will help to keep it under control," says Moore.

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