Evolution

"Ontogeny recapitulates phylogeny" biologists once said - meaning that an animal's "ontogeny", its embryonic development, replays its entire evolutionary history.

Today our understanding a more nuanced and a better way to figure out how animals evolved is to compare regulatory networks that control gene expression patterns, particularly embryonic ones, across species.  But that task can be humbling, according to Stowers Institute for Medical Research Scientific Director Robb Krumlauf, Ph.D. and colleagues, who show that the sea lamprey Petromyzon marinus, a survivor of ancient jawless vertebrates, exhibits a pattern of gene expression that is reminiscent of its jawed cousins, who evolved much, much later.


Gibbons are small, tree-living apes from Southeast Asia, many species of which are endangered. They are part of the same superfamily as humans and great apes, but sit on the divide between Old-World monkeys and the great apes.

These creatures have several distinctive traits, such as an unusually large number of chromosomal rearrangements, and different numbers of chromosomes are seen in individual species.

Researchers recently completed analysis of the mobile elements in the gibbon genome. This included the characterization of the mobile genetic element called LAVA. LAVA is made up of pieces of known jumping genes and named after its main components: L1, Alu, and the VA section of SVA mobile elements.


New whale research has turned a long-accepted evolutionary assumption on its...hips. Instead of  being just vestigial, whale pelvic bones play a key role in reproduction, according to a new study.

Both whales and dolphins have pelvic (hip) bones, evolutionary remnants from when their ancestors walked on land more than 40 million years ago. Common wisdom has long held that those bones are simply vestigial, slowly withering away like tailbones have in humans. But a new paper by USC and the Natural History Museum of Los Angeles County finds that not only do those pelvic bones serve a purpose – but their size and possibly shape are influenced by the forces of sexual selection.

The coffee plant has a newly sequenced genome and that can tell scientists what they really want to know about: the evolution of caffeine.

The sequences and positions of genes in the coffee plant show that they evolved independently from genes with similar functions in tea and chocolate, which also make caffeine. Coffee did not inherit caffeine-linked genes from a common ancestor, but instead developed the genes on its own.

Why Coffee?


In 1986, an expedition off the South-East coast of Australia near Tasmania, from depths of between 400 and 1,000 metres, brought up some jelly-like creatures, which were seen to be unusual and immediately preserved in ethanol. Now they have been examined, and assigned to a new genus Dendrogramma (from their resemblance to a tree diagram), with two species D. enigmatica and D. discoides.

Most living mammals are nocturnal and it has long been thought that the transition to nocturnality occurred at about the same time as mammals evolved, around 200 million years ago. That hypothesis was based on features such as the large brains of mammals (good for processing information from senses like hearing, touch, and smell) and the details of light-sensitive chemicals in the eyes of mammals.

It turns out that nocturnal activity might have a much older origin among ancient mammal relatives, called synapsids.


Why wild animals genetically changed into domesticated forms has long been a mystery, covered by the blanket artificial selection reasoning.

A new paper in Science says that many genes controlling the development of the brain and the nervous system were particularly important for rabbit domestication. 


Although separated by hundreds of millions of years of evolution, flies, worms, and humans share ancient patterns of gene expression and it's all in our genomic data.

Three related studies in Nature, tell a similar story: even though humans, worms, and flies bear little obvious similarity to each other, evolution used remarkably similar molecular toolkits to shape them.

There are dramatic differences between species in genomic regions populated by pseudogenes, molecular fossils of working genes, according to Yale authors in Proceedings of the National Academy of Sciences.


Organisms in a symbiotic relationship will often shed genes as they come to rely on the other organism for crucial functions but researchers have uncovered an unusual event in which a bacterium that lives in a type of cicada split into two species - doubling the number of organisms required for the symbiosis to survive.


If you capture a hummingbird on high-speed video and slow it down, their wings thrum like helicopter blades as they hover near food. Their hearts beat 20 times a second and their tongues dart 17 times a second to slurp from a feeding station.