Recycling old genes to get new traits: How social behavior evolves in bees

Image of sweat bee in tunnel.

(Phys.org/Smithsonian Tropical Research Institute) A team working at the Smithsonian Tropical Research Institute found evidence to support a long-debated mode of evolution, revealing how evolution captures environmental variation to teach old genes new tricks: Sweat bees switch from solitary to social behavior, repurposing ancient sets of genes that originally evolved to regulate the development of other traits.

Genetic identity: A new threat to native bumble bees

Screen shot of the video.

(The Applied Ecologist) In their recently published article, Ignasi Bartomeus and colleagues show how the commercial bumble bee trade is affecting the genetic integrity of native pollinators. They show evidence that hybridization between commercial and native lines is common in southern Spain. What are its implications? What should we do to fix it? They’ve also crafted a wonderful video (with the help of Bartomeus’ kids) to explain it all.

Newly identified gene reduces pollen number of plants

Microscopic image of pollen grains.

(University of Zurich) Producing fewer sperm cells can be advantageous in self-fertilizing plants. An international study led by the University of Zurich has identified a gene in the model plant Arabidopsis that reduces the number of pollen. In addition to supporting the evolutionary theory, these findings could help to optimize plant breeding and domestication in agriculture.

Genetically engineering the perfect bee – in 1892

Black and white image of apiary in orchard.

(Scientific American) “It is said that there are at least two distinct races of stingless bees in South America, but these races have not much value as honey gatherers, and moreover they build combs with very thick-walled cells, and probably they would not be worth cultivating as compared with the European, Asiatic and African races. But if we can cross our bees with the giant bees of India and obtain a race with a long proboscis and perhaps increased size (if that should prove to be of any advantage), and cross this improved race with the South American stingless bees, we shall then have a race of bees which it will be difficult to improve.”

How does an intersex bee behave?

Close up image of gynandromorph bee.

(Smithsonian Tropical Research Institute) In a neotropical forest in Panama, an unusual bee was born. Its form was that of a male on one half and a female on the other half. Given the singularity of the occurrence, the group decided to describe an aspect of its behavior that hadn’t been previously studied in gynandromorphs: the circadian activity – the internal clock that drives an organism’s daily activities.

Wasps’ gut microbes help them – and their offspring – survive pesticides

Close-up image of tiny wasp.

(ScienceDaily/Cell Press) Exposure to the widely used pesticide atrazine leads to heritable changes in the gut microbiome of wasps. Additionally, the altered microbiome confers atrazine resistance, which is inherited across successive generations not exposed to the pesticide. Even though these wasps are not natural crop pollinators, the study could have broad implications. Notably, bacterial atrazine-metabolizing genes are also present in wild bee populations exposed to the pesticide.