Videos of Evolution in Action

[Oxytropidoceras]

Stunning Videos of Evolution in Action

The MEGA-plate allows scientists to watch

bacteria adapting to antibiotics before

their eyes. Ed Yong, The Atlantic.

http://www.theatlantic.com/science/archive/2016/09/stunning-videos-of-evolution-in-action/499136/

 

The Evolution of Bacteria on a “Mega-Plate”

Petri Dish (Kishony Lab), Harvard Medical School

https://www.youtube.com/watch?v=plVk4NVIUh8

 

The Evolution of Bacteria on a “Mega-Plate”

Petri Dish, Harvard Medical School

https://vimeo.com/180908160

 

Yours,

 

Paul H.

[JohnBrewer]

Amazing video Paul, thanks for sharing. 

[Scylla]

Thanks Paul, I love this video. I once had to make 10 x10 inch petri dishes, but this one is just HUGE!

[Raggedy Man]

The experiment being conducted at Michigan State University on Escherichia coli is quite remarkable. I think the resistance to antibiotics on this plate is through plasmids and conjunction not through genetic mutation.

[tmaier]

From the article...

"Baym himself, who has seen the movies hundreds of times, is still blown away by them. “You can actually see mutations happening,” "

Although there might be some mutations happening at the time, many of the bacteria in a strain likely already have the drug resistance. As the population hits the wall of drug-poison, it selects out the resistant ones to proceed further. This is often a minority of the total population, so there is a delay as the population grows with this new genome strain that has the resistance. A side effect is that by grossly winnowing the population like this, many of the benificial genes are lost, and thus the population becomes genetically "bottle-necvked", i.e., they are now weaker to other threats. A bottle neck like this can often lead to extinction (lucky for the patient!).

A gene pool is like a bag of tricks, and when under thrteat or offered a zone of expansion, the population does not have to rely on immediate mutations, it can pull out of the bag some individuals that already have this trait that is needed.

Other genes can be passed on latterally in bacteria (mentioned by @Raggedy Man). They don't do it sexually (like most all eukaryotes), but they can pass genes in other ways. So that means to actually say that a mutation just happened in front of our eyes, we need to know the WHOLE population genome, to make sure it wasn't just selected as a pre-existing gene. Also, saying that a selection event like this is evolution seems to trivialize the long and complex process of evolution to me... but other people do go ahead with using that term, so... whatever...

Bacterial genetics and drug resistant genes http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2937522/

So I thought I should mention, what you see is not all mutation and evolution, and a lot of it is likely to be natural selection of existing traits and a shifting genomtype of the general population. Although there is desire to believe that evolution and life will overcome all obsticacles, that isn't really true, as you can see from all the exinict species who could not find a way through the Petri dish.

DAG_NABBIT! I'm stuck with a low bandwidth connection and can't see this Petri dish video! 35 Years ago I wrote a conputer program that I called "PETRI3D", and it was a 3D version of the old game of "LIFE", only the rules were more biological in nature. The computer game of "LIFE" is an old exercise given to beginning computer programming students, and they have to create a 2D Petri dish, and run it through many generations. It is good practice on writing simulations and working with arrays.

computer game of LIFE, similar to a Petri dish of bacteria
http://www.google.com/search?hl=en&source=hp&biw=&bih=&q=computer+game+of+life&btnG=Google+Search&gbv=1
http://www.google.com/search?q=conway+computer+game+of+life&btnG=Search&hl=en&gbv=1&tbm=isch
If you fish around on the internet you will find some online games of "LIFE".

I'll have to view this video when I go to the library (15 miles away).

[tmaier]

Oh-yeah... I like this part here...

---------------------------

"But as the movie continues, bright spots start appearing within the faint areas. These are bacteria that have picked up “compensatory mutations”, which allow them to grow quickly and resist antibiotics. They ought to have been the fittest microbes on the plate, able to colonise new areas more effectively than their slower-growing peers. But more often than not, they became trapped. Weaker strains at the front of the expanding wave of microbes were already gobbling up all the nutrients, leaving their faster-growing peers with nowhere to grow. “You don’t have to be better than everyone else around you; you just have to be the first in a new area,” says Baym.

It shows the importance of randomness in evolution “in a really beautiful way, a way that is easy to visualize and thus hard to deny,” adds Yeh. “It’s not just that mutations need to arise, it matters very much where those mutation pops up.”"

------------------------------

Peak fitness... BAH_HUMBUG!! :)

A large population becomes like a juggernaut ship, and these "fittest genes" just don't have the sway to change the ship's course. The fittest genes just become deck passengers, playing shuffleboard and drinking mai-tais... enjoying the ride. :)

It explains what is actually seen in nature.

[JohnBrewer]

So cool I had to watch it again