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The Billion Dollar Secrets Inside Tumbleweeds - Video học tiếng Anh
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The Billion Dollar Secrets Inside Tumbleweeds
The Billion Dollar Secrets Inside Tumbleweeds
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Sous-titres (176)
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[Music]
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by my money for security reasons baggage
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unattended will be removed and destroyed
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[Music]
0:57
United Airlines flight 2120 one Denver
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[Music]
2:15
hi I think you're looking for me
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hello Internet's past gray here at a
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hotel in Denver Colorado why well for
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weeks I've been thinking about
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tumbleweed and what started as mild
2:33
curiosity turned into a lot of reading
2:36
and a lot of writing and hopefully a
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video future gray has finished and can
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put on the screen here now in editing
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but for current me it's still a work in
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progress and as part of that I came to
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the research lab here to talk to some of
2:54
the world experts about why tumbleweed
2:56
are so troublesome and the work these
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professors and their students do at the
3:00
weed lab I'm really excited I've run out
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of people who will talk to me about
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tumbleweed in real life this is the kind
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of stuff we do a lot of that's a photo I
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took that is what happens when a mother
3:21
plant tumbles in the wind and then the
3:23
farmer sprays and all of the progeny
3:26
from this mother plant carry a
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resistance gene if the farmer had not
3:33
sprayed if he had not sprayed the whole
3:44
field would have looked green let's just
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do a walking tour of the facility oh by
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the way before I forget that coffee was
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fantastic okay yeah that was great
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oh yeah on the tour I was able to see my
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first tumble tots in person and the
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various tortures weeds are put through
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at the lab to test their strengths and
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weaknesses in a variety of ways
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particularly cold tolerance that I've
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got to experience firsthand and it's
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crazy how tough weeds can be and how
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fast they can adapt here's an example
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where two weeds of the same species were
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sprayed with weed killer the one on the
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left looks like it's doing better but
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that's the one that's going to die
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because the weed on the right has a new
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mutation that lets it push all the we
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Killer into its outmost leaves to
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sacrifice them so the core can survive
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this video was taken just before I
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arrived so I got to see the survivor in
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person so this is the one that got
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sprayed and it totally survives
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now these a beautiful because he's nom
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I'll go yeah right so they all have
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these little pores that survived yeah
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and just the outside parts time yeah
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yeah that's nuts though that this is the
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one you showed me that God loved that I
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thought was doomed I thought this was
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totally doomed and it's growing all up
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to be a big problem and the tumbleweeds
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in particular are insanely adaptive
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talking to the experts all day about the
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terror of tumbleweed and their seemingly
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endless ways to survive I wanted to know
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why is it that some weeds are so much
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better at being weeds it was about the
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genome and just what it is that is
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fascinating about it so you know genetic
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variation is the source of what natural
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selection acts on and that's what
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enables species to respond to changes in
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climate over time imagine that an area
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around Salt Lake where you are and the
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harshest final nips on the planet ready
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and yet tumbleweeds are frightening you
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know if you've seen when these videos
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where they make a media plate that
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contains a different antibiotics in
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series and put the bacteria to start and
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the mutation will happen for existence
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and they'll grow then they hit the next
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one a mutation happens and they grow and
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so on because bacteria divide any 15-20
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minutes
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you know it's happening so much faster
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were kind of asking maybe why one
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species is a better way than other ones
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is and maybe they have a higher rate of
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generating all these sources radiation
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and so extra copies mutations in those
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copies so that's what it is it's not
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just the weed has a gene which can
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metabolize a herbicide is that that weed
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has 50 copies of the same gene which
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means the plant has all these places in
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which
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teachers can possibly occur that
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benefited for processing like the
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different version of the herbicide and
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allowed to survive while still being
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able to keep all of the copies for the
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old version of the herbicide so it
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doesn't have to just like you take that
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one gene in the exact correct way oh
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what a pain in the ass yeah yeah exactly
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our working hypothesis right now is that
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kosha has a genome that is more from the
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mistakes that generate gene duplications
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than other species and that could just
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be really beneficial especially for
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something that is invading a new place
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what makes a difference between just
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dying off and going extinct versus
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propagating across a continent maybe
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they're their error repair and machinery
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has lower fidelity and this generates
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variation that can be adaptive and then
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where it gives us even a bit more
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provocative as does it responds stress
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is that a signal to the plant to relax
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its error repair mechanisms we're not
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going to generate more novel genetic
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variations and we don't really know that
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you get adaptive variation from stress
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in the planet we'd like to test it and
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find out we took or yeah so if we can't
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beat them the question is can we turn
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tumbleweed to our advantage because
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we've done the full genome sequence or
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kosha we want to explore the genes in
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these successful long lasting weeds and
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see if there are traits that we can take
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out of the weeds and use them to improve
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soybeans or corn or cotton or whatever
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if you had to pick the four things that
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I would pull out of a plant like kosher
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so they're cold tolerant they're
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extremely heat tolerant they are also a
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very drought tolerant it tolerates the
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saline soils or salty soils so if you
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could put those four traits together and
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introduce them into crop genomes at the
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global level I'm telling you it would be
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worth billions and billions and billions
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of dollars looking at weeds as more than
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just something to kill and control and
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manage but as a novel source of unique
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genes that could be beneficial
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for food and fuel production well the
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day is ending here and it has totally
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been worth crossing the ocean for my
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brain is completely full of tumbleweed
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talk thanks to the team at the Colorado
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State weed lab but I am exhausted I've
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stayed on GMT so it's much later for me
9:05
here than it normally would be so I hit
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need to get back to the hotel to sleep
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and to process everything to get up
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tomorrow morning to drive to the
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airports and to fly back home to make
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some adjustments to the script based on
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all of the conversations here so that
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future me can finish making that video I
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think it's gonna be a good one I'm
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really excited
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you
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for something like this is as a person
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manually put in each seed in one at a
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time
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holy moly
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