Category Archives: Other

Transgender Algae Reveal Evolutionary Origin of Sexes

Volvox carteri - juvenile (photo by Aurora Nedelcu)

Volvox carteri – juvenile (photo by Aurora Nedelcu)

Main Point:

Throughout evolution, living things have repeatedly developed physically distinct sexes, but how does this actually happen? A discovery in the multicellular green alga, Volvox carteri, has revealed the genetic origin of male and female sexes, showing how they evolved from a more primitive mating system in a single-celled relative.

Published in:

PLOS Biology

Study Further

A team of scientists led by James Umen, Ph.D. , Associate Member, Enterprise Institute for Renewable Fuels at the Danforth Plant Science Center, identified the master regulatory gene for sex determination in Volvox and found that it has acquired new functions compared to a related gene in its close relative, the unicellular alga Chlamydomonas reinhardtii, which does not have physically distinguishable (dimorphic) sexes.  Their findings are publishing in the open access journal PLOS Biology on July 8, and may also provide a possible blueprint for how sexes in other multicellular organisms like plants and animals may have originated.

For plants and animals having male and female reproductive cells or gametes is the norm, and the differences between the two types of gametes are obvious.  Male gametes are small motile sperm or pollen, while female gametes are large egg cells. However, the evolutionary origins of male and female sexes are unclear because the distant unicellular relatives of plants, animals and other multicellular species generally don’t have distinct sexes, but instead have mating types – a system in which gametes of one mating type can only fuse with those with a different mating type, but the cells of each mating type are indistinguishable from each other in size and morphology. Continue reading

“Land grabbing” could help feed at least 300 million people, study suggests

Land grab (Source: tni.org)Main Point:

Crops grown on “land-grabbed” areas in developing countries could have the potential to feed an extra 100 million people worldwide, a new study has shown.

Published in:

Environmental Research Letters

Study Further:

The improved infrastructure brought about by foreign investment could increase the productivity of subsistence farmlands in countries such as Indonesia and Papua New Guinea and could mean these lands can feed at least 300 million people around the world. This is compared to about 190 million people that could be fed if the land was left tended to by the local population.

The findings have been published today, 27 June, in IOP Publishing’s journal Environmental Research Letters. Continue reading

Finding elusive emperor penguins

Penguins (Photo Credit: Robin Cristofari, CNRS/IPEV)

Penguins (Photo Credit: Robin Cristofari, CNRS/IPEV)

Main Point:

Both surveyors and satellites needed to study remote penguin populations.

Published in:

PLOS ONE

Study Further:

Field surveys and satellites complement each other when studying remote penguin populations, according to research published June 25 in the open access journal PLOS ONE by André Ancel from the CNRS at Strasbourg and colleagues. Continue reading

Fish-eating spiders discovered around the world

Spider (Credit: Peter Liley, Moffat Beach, Queensland)

Spider (Credit: Peter Liley, Moffat Beach, Queensland)

Main Point:

Spiders from eight families prey on fish.

Published in:

PLOS ONE

Study Further:

Spiders from five different families prey on small fish in the wild, according to a systematic review published June 18, 2014 in the open-access journal PLOS ONE by Martin Nyffeler from University of Basel, Switzerland, and Bradley Pusey from The University of Western Australia. Continue reading

A Call to Protect Antarctica Better

Antarctica (Credit: cloudzilla/Flickr)Main Point:

With a surge in visitors to Antarctica, Antarctica’s ice-free land needs better protection from human activities, leading environmental scientists say.

Published in:

PLOS Biology

Study Further:

Antarctica has over 40,000 visitors a year, and with more and more research facilities being built in the continent’s tiny ice-free area, the ‘last wilderness on Earth’ is one of the planet’s least-protected regions say Dr Justine Shaw and Professor Hugh Possingham of the National Environmental Research Program’s Environmental Decisions Hub.

“Most of Antarctica is covered in ice, with less than one per cent permanently ice-free. Only 1.5 percent of this ice-free area belongs to Antarctic Specially Protected Areas under the Antarctic Treaty System, yet ice-free land is where the majority of biodiversity occurs,” says Dr Shaw. Continue reading