Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bizarre insect inbreeding signals an end to males: News tips from the American Naturalist

28.07.2011
Bizarre insect inbreeding signals an end to males

A bizarre form of inbreeding could spell the end of males in one insect species, according to researchers from Oxford University. The research focused on cottony cushion scales, a hermaphroditic bug species in which females appear to fertilize their own eggs.

"It turns out that females are not really fertilizing their eggs themselves, but instead are having this done by a parasitic tissue that infects them at birth," said Laura Ross, one of the study's authors. "It seems that this infectious tissue derives from leftover sperm from their fathers." In effect, the tissue enables males to father offspring with both their mates and then their daughters. According to a mathematical model developed by Ross and her co-author Andy Gardner, this odd reproductive tactic could eliminate the need for males in the species. Once the parasitic fathers become widespread in a population, females will be inclined to reproduce with them instead of regular males. Regular males, as a result, become very rare because they have a hard time finding willing mates.

Andy Gardner and Laura Ross, "The Evolution of Hermaphroditism by an Infectious Male-Derived Cell Lineage: An Inclusive-Fitness Analysis."

Without competition, island frogs evolve rapidly

Scientists led by Ben Evans of McMaster University have documented the rapid evolution of new fanged frog species on the island of Sulawesi, near the Philippines. The team found 13 species of fanged frog on the island, nine of which hadn't previously been described. The species differ in body size, amount of webbing in their feet, and even how they raise their young—all in accordance with the demands of their distinct ecological niches. Sulawesi has the same number of fanged frog species as the Philippine archipelago. "We would expect to find more species on the archipelago because it's so much larger, but that's not the case," Evans said. Why such diversity on the smaller island? There's less competition on Sulawesi, the researchers say. Fanged frogs in the Philippines have to compete with another genus of frogs, Platymantis. Platymantis never made to hop over to Sulawesi, leaving the fanged frogs free to spread out into new habitat niches, to which they eventually adapted. The rapid evolution of these frogs is a striking example of adaptive radiation—a concept Charles Darwin famously recorded in Galapagos finches.

Mohammad I. Setiadi, Jimmy A. McGuire, Rafe M. Brown, Mohammad Zubairi, Djoko T. Iskandar, Noviar Andayani, Jatna Supriatna, and Ben J. Evans, "Adaptive Radiation and Ecological Opportunity in Sulawesi and Philippine Fanged Frog (Limnonectes) Communities."

It takes a village, but only in times of plenty

Acorn woodpeckers are cooperative breeders, meaning adult birds often join breeding groups and help raise young that are not their own. Scientists have long thought that communal breeding may have evolved to help birds deal with food shortages and other difficult times. But a study by researchers from Cornell and Gonzaga shows that for acorn woodpeckers, the opposite seems to be true: Help contributed by other family members is beneficial only when the acorn crop is large. "Apparently when the crop is poor, the additional food that helpers provide to nestlings doesn't make up for the extra resources those helpers are using," said Walter Koenig, the study's lead author. "Whereas when the acorn crop is good, their help is enough to significantly increase both the survivorship of the other birds in the group and the number of young the group can fledge. At least in acorn woodpeckers, living together in a family only confers benefits when food is plentiful."

Walter D. Koenig, Eric L. Walters, and Joseph Haydock, "Variable Helper Effects, Ecological Conditions, and the Evolution of Cooperative Breeding in the Acorn Woodpecker."

Bacterial spite: When killing yourself is a good strategy

Spite evolves in close quarters, according to research led by Fredrik Inglis of the University of Oxford and ETH, Zurich. Inglis and his team studied a bacterial species in which individuals sometimes explode, releasing a toxin into the environment that is deadly to competing bacteria. This kamikaze-like behavior is a bit of an evolutionary mystery. How could a behavior in which an individual gives up its chance to reproduce evolve? Inglis and his team had previously developed a mathematical model showing that such spite is quite likely to evolve in bacterial colonies that are clonal, meaning individuals share the same genes. The model shows that if a few individuals sacrifice themselves to take out competitors, they increase the chances that their genes (albeit in other individuals) will be passed to the next generation. Lab experiments performed by Inglis and his team support the model. The experiments further show that spiteful species are most successful when competing with other species for the same resource patch. Spite is far less successful when multiple patches are available. The results, Inglis says, could provide insight into how and when bacteria cause disease.

R. Fredrik Inglis, Patrick Garfjeld Roberts, Andy Gardner, and Angus Buckling, "Spite and the Scale of Competition in Pseudomonas aeruginosa."

For the complete table of contents for the August issue, go to www.journals.uchicago.edu/an.

Since its inception in 1867, The American Naturalist has maintained its position as one of the world's most renowned, peer-reviewed publications in ecology, evolution, and population and integrative biology research. While addressing topics in community and ecosystem dynamics, evolution of sex and mating systems, organismal adaptation, and genetic aspects of evolution, AmNat emphasizes sophisticated methodologies and innovative theoretical syntheses--all in an effort to advance the knowledge of organic evolution and other broad biological principles.

Kevin Stacey | EurekAlert!
Further information:
http://www.uchicago.edu

More articles from Life Sciences:

nachricht Tag it EASI – a new method for accurate protein analysis
20.06.2018 | Max-Planck-Institut für Biochemie

nachricht How to track and trace a protein: Nanosensors monitor intracellular deliveries
19.06.2018 | Universität Basel

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Temperature-controlled fiber-optic light source with liquid core

In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.

Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...

Im Focus: Overdosing on Calcium

Nano crystals impact stem cell fate during bone formation

Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

Creating a new composite fuel for new-generation fast reactors

20.06.2018 | Materials Sciences

Game-changing finding pushes 3D-printing to the molecular limit

20.06.2018 | Materials Sciences

Could this material enable autonomous vehicles to come to market sooner?

20.06.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>