Homoplasy: A good thread to pull to understand the evolutionary ball of yarn

Feb 24, 2011
Homoplasy is a fascinating and unusual occurrence in evolution. It is the independent acquisition of the same trait in unrelated lineages. To understand whether multiple organisms share the same trait because of homoplasy, their places in the evolutionary tree of life must be defined. Parallelism/convergence homoplasy occurs when the same trait is present in two lineages that lack a recent common ancestor. Reversal homoplasy occurs when a trait is present in an ancestor but not its immediate descendants; but appears later in a subsequent descendant. Credit: Zina Deretsky

With the genetics of so many organisms that have different traits yet to study, and with the techniques for gathering full sets of genetic information from organisms rapidly evolving, the "forest" of evolution can be easily lost to the "trees" of each individual case and detail.

A review paper published this week in Science by David Wake, Marvalee Wake and Chelsea Specht, all currently National Science Foundation grantees, suggests that studying examples of homoplasy can help scientists analyze the overwhelming deluge of genetic data and information that is currently being generated.

For example, studying situations where a derived trait surfaces in two lineages that lack a recent , or situations where an ancestral trait was lost but then reappeared many generations later, may help scientists identify the processes and mechanisms of evolution.

The authors provide many fascinating examples of homoplasy, including different species of salamanders that independently, through evolution, increased their body-length by increasing the lengths of individual vertebrae. By contrast, most species grow longer by adding vertebrae through evolution.

The authors also explain how petals in flowers have evolved on six separate occasions in different plants. A particularly striking example of homoplasy cited by the authors is the evolution of eyes, which evolved many times in different groups of organisms--from invertebrates to mammals--all of which share an identical for their eyes.

These kinds of examples of genetic and help scientists elucidate relationships between organisms, as well as develop a fuller picture of their evolutionary history.

Explore further: Rock-paper-scissors model helps researchers demonstrate benefits of high mutation rates

Related Stories

UCSD Biologists Find New Evidence for One-Way Evolution

Jan 18, 2006

By tracing the 30-million year history of variation in a gene found in plants such as tomatoes and tobacco, biologists at the University of California, San Diego have found new evidence to support an old idea ...

'Evolution: A Developmental Approach'

Jan 27, 2011

What separates humans from Chimpanzees? Is it the genetics of our population, or our different structures and behavior capabilities? To Professor Wallace Arthur it is all of these points, which is why his latest book Evolution: A ...

Reverse evolution in real-time

Jan 11, 2009

Evolutionary biology tells us that replaying life's tape will not not look at all like the original. The outcome of evolution is contingent on everything that came before. Now, scientists at the Instituto Gulbenkian de Ciencia ...

Recommended for you

Plants with dormant seeds give rise to more species

Apr 18, 2014

Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster. More ...

Researchers successfully clone adult human stem cells

Apr 18, 2014

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

User comments : 0

More news stories

Biologists help solve fungi mysteries

(Phys.org) —A new genetic analysis revealing the previously unknown biodiversity and distribution of thousands of fungi in North America might also reveal a previously underappreciated contributor to climate ...

Researchers successfully clone adult human stem cells

(Phys.org) —An international team of researchers, led by Robert Lanza, of Advanced Cell Technology, has announced that they have performed the first successful cloning of adult human skin cells into stem ...

NASA's space station Robonaut finally getting legs

Robonaut, the first out-of-this-world humanoid, is finally getting its space legs. For three years, Robonaut has had to manage from the waist up. This new pair of legs means the experimental robot—now stuck ...

Ex-Apple chief plans mobile phone for India

Former Apple chief executive John Sculley, whose marketing skills helped bring the personal computer to desktops worldwide, says he plans to launch a mobile phone in India to exploit its still largely untapped ...

Filipino tests negative for Middle East virus

A Filipino nurse who tested positive for the Middle East virus has been found free of infection in a subsequent examination after he returned home, Philippine health officials said Saturday.

Egypt archaeologists find ancient writer's tomb

Egypt's minister of antiquities says a team of Spanish archaeologists has discovered two tombs in the southern part of the country, one of them belonging to a writer and containing a trove of artifacts including reed pens ...

Airbnb rental site raises $450 mn

Online lodging listings website Airbnb inked a $450 million funding deal with investors led by TPG, a source close to the matter said Friday.