Conflict Between Sexes Could Replace Evolution of New Species

New research shows that males and females of the same species can evolve to be so different that they prevent other species from evolving or colonising habitats, challenging long-held theories on the way natural selection drives the evolution of biodiversity.

According to Darwin’s theory of natural selection, first introduced in his book On the Origin of Species (1859), new environments such as mountains and islands with abundant food and habitats, offer species the ‘ecological opportunity’ to colonise an area using those resources.

New research from the UK has shown that exactly the same mechanism of evolution that creates new species also operates within the same species when males and females compete for the ecological resources available in different habitats, such as bushy areas or stony patches with abundant food. The conflict between the sexes can lead to one sex becoming bigger, more colourful or adapting to eat different food, just like a traditional process of evolution by natural selection can lead an ancestor to split into two different species.

This process of evolution between the sexes expands the biodiversity of the area – a development that evolutionary biologists previously thought only occurred when the number of different species using different resources or ‘niches’ increases. This new research challenges that assumption, showing that different species and different sexes of the same species can occupy these niches.

This new research which explored the evolution of lizards in the Chilean Andes Mountains and Argentinean Patagonia, shows that different sexes of the same species can fill niches as well, meaning new species are actively prevented from evolving.

This is because there is no new environment for them to occupy – a necessary condition for new species to evolve under Darwin’s theory of natural selection.

Conducted by academics from the Universities of Lincoln, Exeter and Sheffield, the study demonstrated that biodiversity can now be seen as the formation of new, different species, or, as the formation of different sexes which are distinct enough to be equivalent to different species in the way they ‘saturate’ ecological niches.

Dr Daniel Pincheira-Donoso, Senior Lecturer in Evolutionary Biology at the School of Life Sciences at the University of Lincoln and lead researcher on the study, said: “Our research reveals evidence for this intriguing phenomenon that the evolution of sexes within a species could replace the evolution of new species, which begins to add a new layer to our understanding of the evolution of biodiversity.

“It is important to stress that the diversity of life on our planet applies not only to the evolution of different species, but also to the independent evolution of males and females within the same species, which potentially has very important implications.”

The findings have been published in the scientific journal Global Ecology and Biogeography.

Article reblogged from here

Darwinism expert to present lecture

One of Britain’s best-known proponents of Darwinism and evolutionary theory will be sharing his typically forthright views at a special event in Lincoln.

Professor of Genetics, science writer, broadcaster and supporter of humanism, Steve Jones, will be giving a lecture entitled “Is Man just another Animal? The View from the Genes” at the University of Lincoln on 5th March, 2013.

Professor Jones is best known to the general public as a broadcaster and writer of popular science books. He has written and presented a Radio 3 series on science and the arts, Blue Skies, and a TV series on human genetics, In the Blood. He also appears on other radio and TV programmes, such as Today, Question Time, In Our Time, Any Questions, Start the Week, Late Review and Newsnight, and writes a regular column in The Daily Telegraph.

As Professor Jones says, he is one of the world’s six greatest experts on the evolutionary genetics of land snails (and the other five agree). He also has an interest in human genetics and evolution and is recognised for his staunch and outspoken defence of science against the “anti-science”, creationism included.

Speaking to The Guardian in 2008, Professor Jones said: “It is my profound hope (likely to be disappointed) that teachers and everyone else should learn to stop treating Darwin as a prophet, or a pariah, or a philosopher, or even as a trained ecclesiastic who turned to atheism – and just take him for what he was, the greatest biologist in history. He made biology into a single science linked by the idea of evolution, rather than a bunch of ideologies.”

Professor Jones is an Emeritus Professor of Human Genetics at the Department of Genetics, Evolution and Environment at University College London and has also held visiting posts at Harvard University, the University of Chicago, the University of California at Davis, University of Botswana, Fourah Bay College in Sierra Leone and Flinders University in Adelaide.

His many awards include the Rhone-Poulenc book prize and the Yorkshire Post first book prize in 1994; the Royal Society Faraday Medal for public understanding of science in 1997; the BP Natural World Book Prize in 1999 and 2000; the Institute of Biology Charter Medal in 2002; and the Irwin Prize for Secularist of the Year in 2006. He is a Fellow of the Royal Society and of the Royal Society of Literature.

Dr Rajiv Machado, who invited Professor Jones to the University, said: “This is a fantastic opportunity for students and staff to hear from one of the best renowned theorists in evolutionary genetics of our generation. We are extremely lucky to have Professor Jones present a lecture to the University and I have no doubt that it will be informative, thought-provoking and progressive.”

Professor Jones will be giving his guest lecture to an invited audience from 4pm in the Co-op Lecture Theatre.

Marine worms reveal the deepest evolutionary patterns

The study of ancient worms could offer a more solid understanding of evolutionary patterns and processes, according to new research.

Scientists from the universities of Bath and Lincoln have revealed new findings on the evolutionary relationships and structure of priapulids – a group of carnivorous mud-dwelling worms living in shallow marine waters.

The research, carried out by evolutionary biologists Dr Matthew Wills, Dr Sylvain Gerber, Mr Martin Hughes (all University of Bath) and Dr Marcello Ruta (University of Lincoln), features in October’s Journal of Evolutionary Biology.

Dr Wills first pioneered a study on existing and extinct priapulids in 1998. Fourteen years on, the team looked at a new and expanded data set of anatomical features to see how knowledge of these worms has been affected by new fossil finds.

He explained: “The fossils from the Cambrian period can cause a real headache for evolutionary biologists. Instinct tells us to expect simple organisms evolving over time to become increasingly more complex. However during the Cambrian period there was an apparent explosion of different major groups of animals, all appearing simultaneously in the fossil record. We looked at priapulid worms, which were among the first ever predators. What’s remarkable is that they had already evolved into a diverse array of forms – comparable to the morphological variety of their living cousins – when we first encounter them in the Cambrian fossil record. It’s precisely this apparent explosion of anatomical diversity that vexed Darwin and famously attracted the attention of Harvard biologist Stephen Jay Gould.”

Dr Ruta, from the School of Life Sciences at the University of Lincoln, continued: “Our work has shown that despite many new fossil finds, including many from China in the last decade, the picture remains largely unchanged. This is really important because the fossil record is notoriously incomplete. It is often difficult to know whether a pattern is just an artifact of this incompleteness, or biologically meaningful. Our study resolutely confirms the latter. Priapulids are fascinating animals with much potential in evolutionary studies. They have a long history, with the earliest known species being 505 million years old, and with some of their extinct relatives being even older. They were important components of ancient bottom-dwelling marine invertebrate communities, and their predatory habits are well documented in the fossil record. However, for all their abundance and diversity, priapulids are a remarkable and often cited example of a morphologically conservative group, their overall shape and proportions having changed relatively little during their history. This research will help us to understand evolutionary patterns in ‘deep time’. This is looking at the tempo (evolutionary rates) and mode (the study of the way, manner or pattern of evolution) to uncover the ancient events when organisms first began to diversify and break from one another. For example, what makes a mammal a mammal and so on.”

The research gives prominence to the importance of an adequate and unbiased inclusion of data, where possible, from both fossil and living species in assembling evolutionary family trees. Fossils inform our understanding of evolutionary patterns and processes, and show unique morphological traits that are no longer observed in living species.

Dr Ruta added: “Detailed scrutiny of other groups of organisms is needed, in order to decipher the rate at which structural, functional and ecological changes occur and how acquisition of new traits impact on group diversification. Ultimately, combined results from these investigations will offer a solid framework for understanding the very roots of Life’s grandeur and the astounding variety of species alive today.”

The full article can be accessed online at http://onlinelibrary.wiley.com/doi/10.1111/jeb.2012.25.issue-10/issuetoc