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The slings and arrows of comparative linguistics

PLOS Biology (new articles) - 19 hours 19 min ago

by Johan J. Bolhuis, Gabriel J. L. Beckers, Marinus A. C. Huybregts, Robert C. Berwick, Martin B. H. Everaert

In this Formal Comment the authors respond to objections to their previous Essay, reiterating that comparative linguistics is not an easy undertaking.
Categories: Biology, Journals

Resistance gained, resistance lost: An explanation for host–parasite coexistence

PLOS Biology (new articles) - 19 hours 19 min ago

by Britt Koskella

Host populations are under continual selection by parasites due to reduced fitness of infected individuals relative to uninfected individuals. This should select for host resistance against parasites, and ample evidence from the laboratory and natural populations demonstrates that hosts can respond rapidly to parasitism by evolving resistance. Why then do parasites still exist? In part, this is due to ongoing arms races as parasites evolve counteradaptations to overcome resistance and to the presence of spatial structure and refuges. However, host–parasite coexistence can also be explained through loss of resistance over time due either to selection against costly resistance mechanisms or constant loss of resistance via reversion mutations.
Categories: Biology, Journals

Evolutionary emergence of infectious diseases in heterogeneous host populations

PLOS Biology (new articles) - 19 hours 19 min ago

by Hélène Chabas, Sébastien Lion, Antoine Nicot, Sean Meaden, Stineke van Houte, Sylvain Moineau, Lindi M. Wahl, Edze R. Westra, Sylvain Gandon

The emergence and re-emergence of pathogens remains a major public health concern. Unfortunately, when and where pathogens will (re-)emerge is notoriously difficult to predict, as the erratic nature of those events is reinforced by the stochastic nature of pathogen evolution during the early phase of an epidemic. For instance, mutations allowing pathogens to escape host resistance may boost pathogen spread and promote emergence. Yet, the ecological factors that govern such evolutionary emergence remain elusive because of the lack of ecological realism of current theoretical frameworks and the difficulty of experimentally testing their predictions. Here, we develop a theoretical model to explore the effects of the heterogeneity of the host population on the probability of pathogen emergence, with or without pathogen evolution. We show that evolutionary emergence and the spread of escape mutations in the pathogen population is more likely to occur when the host population contains an intermediate proportion of resistant hosts. We also show that the probability of pathogen emergence rapidly declines with the diversity of resistance in the host population. Experimental tests using lytic bacteriophages infecting their bacterial hosts containing Clustered Regularly Interspaced Short Palindromic Repeat and CRISPR-associated (CRISPR-Cas) immune defenses confirm these theoretical predictions. These results suggest effective strategies for cross-species spillover and for the management of emerging infectious diseases.
Categories: Biology, Journals

Midgut-derived neuropeptide F controls germline stem cell proliferation in a mating-dependent manner

PLOS Biology (new articles) - 19 hours 19 min ago

by Tomotsune Ameku, Yuto Yoshinari, Michael J. Texada, Shu Kondo, Kotaro Amezawa, Goro Yoshizaki, Yuko Shimada-Niwa, Ryusuke Niwa

Stem cell maintenance is established by neighboring niche cells that promote stem cell self-renewal. However, it is poorly understood how stem cell activity is regulated by systemic, tissue-extrinsic signals in response to environmental cues and changes in physiological status. Here, we show that neuropeptide F (NPF) signaling plays an important role in the pathway regulating mating-induced germline stem cell (GSC) proliferation in the fruit fly Drosophila melanogaster. NPF expressed in enteroendocrine cells (EECs) of the midgut is released in response to the seminal-fluid protein sex peptide (SP) upon mating. This midgut-derived NPF controls mating-induced GSC proliferation via ovarian NPF receptor (NPFR) activity, which modulates bone morphogenetic protein (BMP) signaling levels in GSCs. Our study provides a molecular mechanism that describes how a gut-derived systemic factor couples stem cell behavior to physiological status, such as mating, through interorgan communication.
Categories: Biology, Journals

Genetic tool that wipes out malaria could save 500,000 lives each year

Genetics - Mon, 2018-09-24 17:00
Malaria could be eliminated by a CRISPR 'gene drive' that wipes out the mosquitoes that spread it, transforming the lives of hundreds of millions of people for the better
Categories: Biology

Genetic tool that wipes out malaria could save 500,000 lives each year

HIV and AIDS - Mon, 2018-09-24 17:00
Malaria could be eliminated by a CRISPR 'gene drive' that wipes out the mosquitoes that spread it, transforming the lives of hundreds of millions of people for the better

People are more clued up about science than you might think

Genetics - Mon, 2018-09-24 12:00
Fake news isn't making us wilfully ignorant. Our survey suggests that people are better informed and more discerning than we give them credit for
Categories: Biology

People are more clued up about science than you might think

HIV and AIDS - Mon, 2018-09-24 12:00
Fake news isn't making us wilfully ignorant. Our survey suggests that people are better informed and more discerning than we give them credit for

People are more clued up about science than you might think

Genetically modified organisms (GMO) - Mon, 2018-09-24 12:00
Fake news isn't making us wilfully ignorant. Our survey suggests that people are better informed and more discerning than we give them credit for
Categories: Science and society

Japanese space hoppers reveal glorious sci-fi vision of asteroid Ryugu

Genetics - Mon, 2018-09-24 09:41
Japan's Hayabusa 2 spacecraft has released its two small MINERVA-II rovers on to the surface of the asteroid Ryugu, and the pair have sent back some amazing images
Categories: Biology

Japanese space hoppers reveal glorious sci-fi vision of asteroid Ryugu

HIV and AIDS - Mon, 2018-09-24 09:41
Japan's Hayabusa 2 spacecraft has released its two small MINERVA-II rovers on to the surface of the asteroid Ryugu, and the pair have sent back some amazing images

Japanese space hoppers reveal glorious sci-fi vision of asteroid Ryugu

Genetically modified organisms (GMO) - Mon, 2018-09-24 09:41
Japan's Hayabusa 2 spacecraft has released its two small MINERVA-II rovers on to the surface of the asteroid Ryugu, and the pair have sent back some amazing images
Categories: Science and society

A man with paralysis can walk again thanks to a nerve-boosting implant

Genetics - Mon, 2018-09-24 09:35
Advances in implants that read signals from the brain and spine are helping people with paralysis to regain the use of their limbs
Categories: Biology

A man with paralysis can walk again thanks to a nerve-boosting implant

HIV and AIDS - Mon, 2018-09-24 09:35
Advances in implants that read signals from the brain and spine are helping people with paralysis to regain the use of their limbs

Riemann hypothesis likely remains unsolved despite claimed proof

Genetics - Mon, 2018-09-24 09:30
Mathematician Michael Atiyah has presented his claimed proof of one of the most famous unsolved problems in maths, but others remain cautiously sceptical
Categories: Biology

Riemann hypothesis likely remains unsolved despite claimed proof

HIV and AIDS - Mon, 2018-09-24 09:30
Mathematician Michael Atiyah has presented his claimed proof of one of the most famous unsolved problems in maths, but others remain cautiously sceptical

10 mysteries of the universe: Is our solar system normal?

Genetics - Mon, 2018-09-24 09:00
Puffball planets the density of polystyrene are just some of the oddities we’ve spied in other solar systems – is our own backyard the exception, not the rule?
Categories: Biology

10 mysteries of the universe: Is our solar system normal?

Genetically modified organisms (GMO) - Mon, 2018-09-24 09:00
Puffball planets the density of polystyrene are just some of the oddities we’ve spied in other solar systems – is our own backyard the exception, not the rule?
Categories: Science and society

10 mysteries of the universe: What is dark matter?

Genetically modified organisms (GMO) - Sun, 2018-09-23 13:00
It’s invisible, and yet the motions of galaxies suggest it must be there. But a recent discovery has just deepened the mystery of the universe we cannot see
Categories: Science and society

10 mysteries of the universe: What is dark matter?

Genetics - Sun, 2018-09-23 13:00
It’s invisible, and yet the motions of galaxies suggest it must be there. But a recent discovery has just deepened the mystery of the universe we cannot see
Categories: Biology