Biologists watch speciation in a laboratory flask

Biologists watch speciation in a laboratory flask
Molecular models of the two receptors the virus evolved to specialize on. Credit: Justin Meyer, UC San Diego

Biologists have discovered that the evolution of a new species can occur rapidly enough for them to observe the process in a simple laboratory flask.

In a month-long experiment using a harmless to humans, biologists working at the University of California San Diego and at Michigan State University documented the evolution of a virus into two incipient species—a process known as speciation that Charles Darwin proposed to explain the branching in the tree of life, where one species splits into two distinct species during evolution.

"Many theories have been proposed to explain speciation, and they have been tested through analyzing the characteristics of fossils, genomes, and natural populations of plants and animals," said Justin Meyer, an assistant professor of biology at UC San Diego and the first author of a study that will be published in the December 9 issue of Science. "However, speciation has been notoriously difficult to thoroughly investigate because it happens too slowly to directly observe. Without direct evidence for speciation, some people have doubted the importance of evolution and Darwin's theory of natural selection."

Meyer's study, which also appeared last week in an early online edition of Science, began while he was a doctoral student at Michigan State University, working in the laboratory of Richard Lenski, a professor of microbial ecology there who pioneered the use of microorganisms to study the dynamics of long-term .

"Even though we set out to study speciation in the lab, I was surprised it happened so fast," said Lenski, a co-author of the study. "Yet the deeper Justin dug into things—from how the viruses infected different hosts to their DNA sequences—the stronger the evidence became that we really were seeing the early stages of speciation."

"With these experiments, no one can doubt whether speciation occurs," Meyer added. "More importantly, we now have an experimental system to test many previously untestable ideas about the process."

To conduct their experiment, Meyer, Lenski and their colleagues cultured a virus—known as "bacteriophage lambda"—capable of infecting E. coli bacteria using two receptors, molecules on the outside of the cell wall that viruses use to attach themselves and then infect cells.

When the biologists supplied the virus with two types of cells that varied in their receptors, the virus evolved into two , one specialized on each receptor type.

"The virus we started the experiment with, the one with the nondiscriminatory appetite, went extinct. During the process of , it was replaced by its more evolved descendants with a more refined palette," explained Meyer.

Why did the new viruses take over?

"The answer is as simple as the old expression, 'a jack of all trades is a master of none'," explained Meyer. "The specialized viruses were much better at infecting through their preferred receptor and blocked their 'jack of all trades' ancestor from infecting cells and reproducing. The survival of the fittest led to the emergence of two new specialized viruses."

Meyers's study was conducted over six years in two separate labs. The first experiments were performed at Michigan State, supported in part by BEACON, the National Science Foundation's Center for the Study of Evolution in Action, and the analyses were completed at UC San Diego.


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More information: J. R. Meyer et al, Ecological speciation of bacteriophage lambda in allopatry and sympatry, Science (2016). DOI: 10.1126/science.aai8446
Journal information: Science

Citation: Biologists watch speciation in a laboratory flask (2016, November 29) retrieved 23 July 2019 from https://phys.org/news/2016-11-biologists-speciation-laboratory-flask.html
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Nov 29, 2016
Doesn't Impress me at all. They say EVERYTHING is in Brain. They are Focused upon AI, Aritificial Intelligence since ONLY a couple of years attempting to Export Human Knowledge from our Brains TO Machines!
Why Not start with smaller Lab Animals & SUCCESSFULLY Transplant Brains in between Small/Smallest Lab Animals and see whether Importing/Exporting Bookmarks from Browser To Browser Works! I DO KNOW KNOW IT IS SHEER STUPID Proposition, but we have Millennia ahead of us. So, Start NOW with a Positive Attitude. MY Suggestion is DON'T UNDERESTIMATE ANIMALS. They are Trillion Times MORE POWERFUL Than us Humans in Their Own Ways!

Nov 29, 2016
@betterexists:
that is one random rant you just went off on, completely unrelated to the article. Nice work.

Nov 29, 2016
Ah, but this is MICRO speciation - it certainly can't apply to large organisms like primates... ;)

Nov 30, 2016
All informed creationists know that speciation takes place and and that it can be observed to occur very fast. In many cases it can take only a few generations. In fact, rapid speciation is critical for the understanding post-Flood diversity. Thus, it is an integral part of biblical creationist thinking. Speciation has been observed many times and it surely doesn't need millions of years. This study only validates even more biblical creationist thinking. The problem for evolutionary speculation is that speciation has never (and can never) be observed to transform one kind into another different and more complex kind. That has to be imagined. It cannnot be tested in the lab or in the field, Lenski experiments notwithstanding. Speciation is an observable reality, but particles to people evolution is nothing but unobservable naturalistic fantasy.

Nov 30, 2016
"With these experiments, no one can doubt whether speciation occurs,"

Don't count on it. Many people will rather fabricate (and live in) a fantasy if the alternative challenges a deeply held belief.

Nov 30, 2016
All informed creationists know that speciation takes place and and that it can be observed to occur very fast.
There was Speciation even in Spiritualism. Read Today's Story, The lead pages, bound like a ring binder, were first discovered in 2008

Nov 30, 2016
There was Speciation even in Spiritualism. Read Today's Story, The lead pages, bound like a ring binder, were first discovered in 2008

I don't know what kind of drugs you are on...but you should definitely take less. Your posts make no sense (and they also invariably have nothing to do with the articles you post on)
Stop it.
Please.

Nov 30, 2016
All informed creationists know that speciation takes place and and that it can be observed to occur very fast.
There was Speciation even in Spiritualism. Read Today's Story, The lead pages, bound like a ring binder, were first discovered in 2008

It is a DailyMail news article dated today

Nov 30, 2016
And yet we see the inherent risk of specialization in mammals... I think repetition and duration extension of this experiment would yield different results.

Nov 30, 2016
And yet we see the inherent risk of specialization in mammals.

It's risk vs. reward. A specialist can overcome a generalist - at the cost of limiting his niche. If the niche disappears (for whatever reason) then the specialist dies with it. Even in a very stable ennvironment: if you specialize to a too small niche then tiny fluctuations can mean the end of a species.

One of my favorite lines from the movie "Ghost in the Shell":
Overspecialize, and you breed in weakness


So it's not really a question of whether a generalist is better or a specialist. A specialist can be highly successfull IF he can go back to being a generalist when needed. But that is a very costly path (in terms of energy expenditure), so it is one that is not often found in nature - as it doesn't tend to survive fierce competition.

Dec 05, 2016
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