Evolution

Parasitic bacteria were the first cousins of mitochondria, the energy factories in our cells – and first acted as energy parasites in those cells before becoming beneficial, according to a University of Virginia study that used next-generation DNA sequencing technologies to decode the genomes of 18 bacteria that are close relatives of mitochondria.


What's not red and about the size of your thumb?

Tomatoes, before ancient scientists set out to make them patabale.  This genomic history of tomato breeding, based on sequencing of 360 varieties of the tomato plant, has vaulted beyond the first tomato genome sequence completed just two years ago. It will lend insight into science for people who believe genetic modification only began happening during the Clinton administration.

Analysis of the genome sequences of these 360 varieties and wild strains shows which regions of the genome were under selection during domestication and breeding. The study identified two independent sets of genes responsible for making the fruit of modern commercial tomatoes 100 times larger than their wild ancestors.



A female neriid fly (right) laying eggs, while her mate fights off a rival male. Angela Crean and Russell Bonduriansky. Credit: Author provided

By Angela Crean and Russell Bonduriansky

The evolution of new traits with novel functions has long been studied by evolutionary biology and a new study of the color markings of cichlid fish has shed some new light on it.

Swiss scientists writing in Nature Communications show what triggered these evolutionary innovations, namely: a mobile genetic element in the regulatory region of a color gene.  


In the past, researchers have primarily used the genetic history of mothers to understand evolution in animals, but a new study has investigated ancestry across the red fox genome, including the Y chromosome (paternal line) and  found some surprises about the origins, journey and evolution of the red fox, the world's most widely distributed land carnivore.

Conventional thinking based on maternal genetics suggested that red foxes of Eurasia and North America composed a single interconnected population across the Bering land bridge between Asia and Alaska.



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.