Evolution


Sparkling Violetear.
Image courtesy of Paul Martin

By Katharine Gammon, Inside Science

(Inside Science) – Most of the time, for an individual animal, the bigger you are, the more likely you are to succeed. But sometimes, the little guy prevails – and scientists are just starting to understand how and when this happens.

“While there has been research on body size and aggressive conflict, no one had looked at why small species can prevail,” said Paul Martin, a biologist at Queen’s University in Kingston, Ontario.



I have just downloaded a paper featuring some research from the University of Durham and our own School of Biological Sciences here at Reading:


TNL1

The idea of evolutionary imbalance when it comes to invasive species is not new, Charles Darwin articulated it. 

The concept is that species from regions with deep and diverse evolutionary histories are more likely to become successful invaders in regions with less deep, less diverse evolutionary histories. Darwin's original insight was that the more challenges a region's species have faced in their evolution, the more robust they'll be in new environments.

To predict the probability of invasiveness, ecologists
Dov Sax of Brown University and Jason Fridley of Syracuse University


Seedless watermelon, salmon, and strawberries all have one thing in common - unlike most eukaryotic multicellular organisms that have two sets of chromosomes, these organisms are all polyploid, meaning they have three or more sets of chromosomes. Seedless watermelon and salmon have 3 and 4 sets of chromosomes, respectively, while strawberries have 10.

Most plant species are polyploid. Polyploidy, or genome doubling, was first discovered over a century ago, but only recently, with the development of molecular tools, has it been revealed just how ubiquitous it is. Polyploidy is being increasingly recognized as an important evolutionary force that can facilitate positive adaptations, lead to instant speciation, and increase biodiversity. 


In a region where modern humans are believed to have originated roughly 200,000 years ago,    DNA from the skeleton of a man who lived 2,330 years ago has a DNA profile that places it among the 'earliest diverged' – oldest in genetic terms – found to-date. 

Somehow the group broke off early in human evolution and became geographically isolated so the skeleton is modern, but its DNA is old.

Astronomers have discovered an unusual carbon-based molecule – one with a branched structure – contained within a giant gas cloud in interstellar space -  27,000 light years away. Like finding a molecular needle in a cosmic haystack, astronomers have detected radio waves emitted by isopropyl cyanide. The discovery suggests that the complex molecules needed for life may have their origins in interstellar space.

Using the Atacama Large Millimeter/submillimeter Array (ALMA), researchers studied the gaseous star-forming region Sagittarius B2.


A key indicator of how successfully one species of monkey will breed can be determined by skin color, a new study has shown. Skin coloration in male and female rhesus macaques is an inherited quality – the first example of heritability for a sexually-selected trait to be described in any mammal.

The team collected more than 250 facial images of free-ranging rhesus macaques, which are native to South, Central and Southeast Asia and which display red skin coloring around the face, as well as the genital and hind-quarter areas.


So much for patriarchy. When it comes to evolution, female populations have always been larger than male populations throughout human history, according to a new study in Investigative Genetics which used paternal genetic information to analyse the demographic history of males and females in worldwide populations.


A new study uses tree rings to document arroyo evolution along the lower Rio Puerco and Chaco Wash in northern New Mexico.