Flies, genes and behavior | Maria de la Paz Fernandez | TEDxRiodelaPlata
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0:21 - 0:24Behavior is written in the genes.
-
0:24 - 0:29All of us have innate behaviors;
all animals are born with behaviors. -
0:29 - 0:33Behaviors which through evolution
have become more complex. -
0:34 - 0:35In many aspects,
-
0:35 - 0:39behavior in males and females
of the same species is different. -
0:39 - 0:40These differences in behavior
-
0:41 - 0:44are due to differences in the wiring
of the nervous system. -
0:44 - 0:48At the same time, these differences
in wiring are established genetically. -
0:48 - 0:52Aggression is a behavior
that in general is specific to males. -
0:52 - 0:54We see it in species
that are very different, -
0:54 - 0:56evolutionarily apart from each other.
-
0:56 - 0:59The way each one
of these species fights is different -
0:59 - 1:01but the mechanisms are similar
-
1:01 - 1:03and the reasons are almost
always the same. -
1:03 - 1:06Males fight for females,
for food, or for territory. -
1:08 - 1:10I study aggression in flies.
-
1:13 - 1:15You are about to see an attack.
-
1:18 - 1:19One animal is going to stand up
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1:19 - 1:22and is going to hurl its body-weight
at his opponent. -
1:26 - 1:28The other one, meanwhile,
is going to try to escape. -
1:29 - 1:31Why do I study aggression in flies?
-
1:31 - 1:34Because the behavior,
that I'm interested in understanding, -
1:34 - 1:36is the same, and the system
is much simpler. -
1:36 - 1:37It's like studying a model.
-
1:39 - 1:41Sometimes it happens
that the other animal, -
1:41 - 1:45instead of escaping,
stays and starts to fight. -
1:47 - 1:49And then something
we call "boxing" occurs. -
1:57 - 2:01Something crucial about attacking
is that only the males do it. -
2:01 - 2:04The one who attacks first
is much more likely to win. -
2:04 - 2:06And males only attack other males.
-
2:06 - 2:08Females never attack.
-
2:12 - 2:15So, why study behavior in flies?
-
2:15 - 2:17Because their behaviors
are the same as ours: -
2:17 - 2:22flies sleep, eat, court, fight,
learn, and remember. -
2:22 - 2:24The nervous system is much simpler;
-
2:24 - 2:28and the genes that play a role,
in this behavior are very similar. -
2:28 - 2:32So, studying aggression in flies
allows us to understand -
2:32 - 2:35how this behavior develops
in other species. -
2:36 - 2:42A key element when deciding
whether to court or attack -
2:42 - 2:45is determining the sex
of the other animal. -
2:45 - 2:49All males are programmed to decide
between courtship or aggression, -
2:49 - 2:51but the sensory signals they use
-
2:51 - 2:55to see if what is in front of them
is a male or a female are different; -
2:55 - 2:58for example, in our species
visual signals are very important. -
3:00 - 3:02This is what a fly has in front of itself.
-
3:05 - 3:07So, how does it decide?
-
3:08 - 3:10Evidently, it somehow makes a decision
-
3:10 - 3:13because what it is going to do
is very different in each case. -
3:13 - 3:16When there is a male
entering its territory, -
3:16 - 3:18it is going to start attacking
-
3:18 - 3:22and to chase him everywhere
until the other one decides to escape. -
3:23 - 3:26When there is a female,
he extends his wing for her. -
3:26 - 3:28As you can see, he literally courts her.
-
3:31 - 3:32He chases her everywhere,
-
3:32 - 3:35he sings to her
until he has finally won her over. -
3:37 - 3:39So the question is, how does it know?
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3:40 - 3:41How does it decide?
-
3:41 - 3:46What are the key signals that it uses
to decide if it has to court or attack? -
3:47 - 3:51If we can identify these signals,
can we change them? -
3:51 - 3:53Can we invert this decision?
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3:53 - 3:55In insects, like in many species,
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3:55 - 3:58chemical signals called pheromones
are very important. -
3:58 - 4:02These signals are produced
by one animal and detected by another. -
4:03 - 4:05So, then something we decided to do
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4:05 - 4:08was to switch the pheromones,
change the scent. -
4:08 - 4:09To make it happen,
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4:09 - 4:13we manipulated the expression
of one gene, called "transformer". -
4:14 - 4:18"Transformer" is turned on in females
and turned off in males. -
4:18 - 4:24So, something that we can do
is to mute the "transformer" in females -
4:24 - 4:26and force its acquisition in males.
-
4:26 - 4:30In doing so, we masculinize females
and feminize males. -
4:30 - 4:34But not all over, we aren't going
to manipulate the entire animal. -
4:34 - 4:36We are going to choose certain parts,
-
4:36 - 4:39in particular the cells
which produce pheromones. -
4:39 - 4:44What we can achieve are females
that have masculine pheromones -
4:44 - 4:47or males that have feminine pheromones;
-
4:47 - 4:52then we are going to see what happens
when a normal male, unmanipulated, -
4:52 - 4:55meets a female
that has masculine pheromones. -
4:57 - 4:58This is what happens, it attacks her.
-
4:59 - 5:01When she enters his territory,
he does something -
5:01 - 5:04that he would never do
in front of a normal female, -
5:04 - 5:05which is start attacking her.
-
5:07 - 5:09When we carried out
the reciprocal experiment, -
5:09 - 5:13what we found was that males
with feminine pheromones were courted. -
5:16 - 5:17What does this mean?
-
5:18 - 5:22That males are genetically
programmed to court -
5:22 - 5:24when they find feminine pheromones
-
5:24 - 5:27and to attack when they find
masculine pheromones. -
5:28 - 5:31But, this behavior,
-
5:31 - 5:35this innate behavior
that is wired in the brain -- -
5:35 - 5:38court if there are feminine pheromones,
-
5:38 - 5:40attack if there are
masculine pheromones -- -
5:40 - 5:42can it be changed?
-
5:42 - 5:46Could it be that an animal
as simple as a fly -
5:46 - 5:50could learn from its experience
and modify a behavior which is innate, -
5:50 - 5:53something which is wired
in its nervous system? -
5:54 - 5:58To respond to this question,
we did a similar experiment. -
5:58 - 6:00Again, we manipulated the "transformer",
-
6:00 - 6:02but this time, in the females' brains.
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6:03 - 6:07These females still have
feminine pheromones -
6:07 - 6:09but they act like males.
-
6:09 - 6:13We muted their "transformer" in the brain
to turn them into aggressive females. -
6:13 - 6:17They not only dislike courtship
completely but they also attack. -
6:18 - 6:20We then asked ourselves,
-
6:20 - 6:23what is a male going to do
when it meets a female -
6:23 - 6:26that has female pheromones
but is aggressive? -
6:26 - 6:29The first thing it's going to do
is court her as much as possible. -
6:29 - 6:33It chases and chases her,
extends its wing, sings to her, -
6:33 - 6:36but the moment comes
when he decides to change his behavior. -
6:37 - 6:39The moment comes
after so much ineffective courting -
6:39 - 6:42and in addition to being attacked by her;
-
6:42 - 6:44he says, "Enough is enough"
and ends up attacking her. -
6:45 - 6:49This means that even an animal
as simple as a fly -
6:49 - 6:54can learn from its experience
and modify its behavior. -
6:54 - 6:55And not only that.
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6:55 - 7:00When there are fights between two males,
there is always a winner and a loser. -
7:00 - 7:02After a male loses many times
-
7:02 - 7:05what happens is that
he suppresses this behavior. -
7:05 - 7:06He stops fighting.
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7:08 - 7:12This means that even in an animal
as simple as a fly -
7:12 - 7:14not only behavior is in the genes,
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7:14 - 7:18but the ability to learn from experience
and modify it is there, too. -
7:18 - 7:19Thank you very much.
-
7:19 - 7:21(Applause)
- Title:
- Flies, genes and behavior | Maria de la Paz Fernandez | TEDxRiodelaPlata
- Description:
-
Humans, sophisticated as we are, can learn and grow beyond our genetic programming. But can flies? María de la Paz Fernández studies how male and female flies perform their standard dance of courtship and aggression -- and tests what might make them modify their behavior.
- Video Language:
- Spanish
- Team:
- closed TED
- Project:
- TEDxTalks
- Duration:
- 07:40
Helene Batt edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
Amaranta Heredia Jaén edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
janet dragojevic edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
janet dragojevic edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
janet dragojevic edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
Helene Batt edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
Helene Batt edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata | ||
Helene Batt edited English subtitles for Moscas, genes y comportamiento: Maria de la Paz Fernandez at TEDxRiodelaPlata |
Ivana Korom
Hi. I'm returning the translation for improvement. Please edit the description of the talk, so it contains only 1-2 sentences describing the actual talk, and not the speaker or the event. You will see that I deleted the information about TEDx.
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Lines are too long and need to be edited. The maximum length of a subtitle is 84. I corrected the subtitles that were over this limit. Note: in the new editor, you can see the character length of each subtitle, as well as its reading speed (characters/second). For languages based on the Latin alphabet, the maximum subtitle length is 84 characters (subtitles over 42 characters need to be broken into two lines). The maximum reading speed should be less than 22 characters per second. You can access the new editor by clicking "Beta: Save and open in new editor" after opening the task in the old interface. To learn more about line length, line breaking and reading speed, watch this tutorial: http://www.youtube.com/watch?v=yvNQoD32Qqo I have also made some edits to the lines, so you can see how to proceed.
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If you need any help, please join the groups I translate TED talks or I transcribe TEDx talks on Facebook; or watch our learning series on YouTube: https://www.youtube.com/watch?v=Nua96nvklF4&list=PLuvL0OYxuPwxQbdq4W7TCQ7TBnW39cDRC Thanks!
Mary Beth Strawn
Hi Ivana, Thank you for your helpful comments! I would love to edit my work, but I can't find this task open. Meaning I can't figure out how to get back into the subtitling program. Any helpful hints? Thanks again, Mary Beth
Ivana Korom
Hello Mary Beth, actually the task went back to the reviewer, Sara Albaladejo. Sara should make these changes, since she's the reviewer. Let's wait some time and if she doesn't have time or can't complete the task for some reason, we'll find a solution. Thanks!
Mary Beth Strawn
Ok great, thanks for the explanation. I'm still new, obviously. :)