Skip to 7:07 if you're just here for a reminder of gene flow. You're ideas of the term are probably right though considering the definition is in the name.
The topics of genetic variation, gene flow, and the emergence of new species are fundamental concepts in evolutionary biology, providing insight into the mechanisms that drive biodiversity and shape the natural world. These processes, often interrelated, play crucial roles in the adaptation and diversification of organisms over time. Genetic Variation: Genetic variation refers to the differences in DNA sequences among individuals within a population. This variation is the raw material upon which natural selection acts, enabling populations to adapt to changing environments. Genetic diversity can arise from mutations, recombination during sexual reproduction, and other genetic processes. Without genetic variation, evolution cannot occur because there would be no new traits for natural selection to act upon. This variation is crucial for the survival of species, as it provides the adaptability needed to thrive in different environments or to resist diseases and other challenges. For example, populations with high genetic diversity are more likely to survive changes in climate or new pathogens, while populations with low diversity may face higher risks of extinction due to their lack of adaptive potential. Gene Flow: Gene flow, also known as genetic migration, is the transfer of genetic material between populations of the same species. It occurs when individuals from different populations interbreed, introducing new genetic material into the gene pool. Gene flow can increase genetic diversity within a population, reduce genetic differences between populations, and prevent the buildup of genetic divergence that might lead to speciation. Gene flow is essential in maintaining the genetic health of populations by counteracting the negative effects of inbreeding, such as the expression of harmful recessive traits. However, it can also limit the formation of new species because it homogenizes populations and reduces the likelihood of genetic divergence. On the other hand, gene flow can also introduce new traits into a population, which can help drive adaptation. For instance, if individuals from a population living in a resource-rich environment mate with individuals from a population living in a harsher environment, the offspring may inherit a combination of traits that allow them to survive in more challenging conditions. New Species and Speciation: Speciation is the process by which new species arise, typically as a result of genetic divergence between populations. When populations of the same species become isolated-geographically, ecologically, or behaviorally-they can begin to accumulate genetic differences over time, leading to the emergence of new species. This divergence can be driven by mutations, natural selection, genetic drift, and a lack of gene flow between the isolated populations. There are two primary forms of speciation: 1. Allopatric Speciation: Occurs when populations are geographically isolated, preventing gene flow. Over time, genetic differences accumulate between the populations, leading to reproductive isolation and the formation of new species.
2. Sympatric Speciation: Happens without geographic isolation. Instead, speciation occurs within a single population due to ecological or behavioral differences, such as shifts in habitat use or mating preferences. This can lead to reproductive isolation, even in the absence of physical barriers. The genetic and ecological factors that drive speciation are complex and depend on many variables, including mutation rates, environmental pressures, and social behaviors within populations. Gene flow, in this context, can either hinder or facilitate speciation, depending on the degree of genetic divergence and the presence of reproductive barriers. Interaction Between Genetic Variation, Gene Flow, and Speciation: The interplay between genetic variation, gene flow, and speciation is key to understanding how new species arise and how biodiversity is maintained. Genetic variation provides the raw material for adaptation, while gene flow can either promote or impede the differentiation of populations. When gene flow is limited or absent, genetic divergence increases, setting the stage for speciation. On the other hand, if gene flow is high between populations, it can slow or prevent speciation by mixing genetic material, preventing the accumulation of differences necessary for the development of reproductive isolation. In cases of hybridization, where individuals from different species interbreed, gene flow can sometimes lead to the formation of new species, either through the establishment of hybrids that have distinct characteristics or through the process of polyploidy (especially in plants). Conclusion: The processes of genetic variation, gene flow, and speciation are intertwined, and their interactions are fundamental to the evolutionary processes that drive the diversity of life. Genetic variation provides the foundation for evolutionary change, gene flow acts as a force of both homogenization and potential adaptation, and speciation is the ultimate outcome of these forces when populations diverge sufficiently to become distinct species. Understanding these processes is crucial not only for studying evolutionary biology but also for applying this knowledge to fields like conservation biology, agriculture, and medicine, where maintaining genetic diversity and preventing the loss of species are of paramount importance.
Great video and nice job! Thank you! I do have a question regarding the "randomness" -- when we look at how the cell reproduce,how DNA replicates and how the stars and atoms move, we really don't see too much randomness there. What is your definition / examples of randomness? Many Thanks!
If 2 human populations were separated without the ability to interbreed, with very different environments, how long would it take for differences to develop so that they could not interbreed if they met?
Let's look at what some secular scientists have had to say that disagrees with evolutionism. We are told that beneficial mutations are an essential mechanism for evolution to occur, but H. J. Muller, who won a Nobel Prize for his work on mutations, said.... "It is entirely in line with the accidental nature of mutations that extensive tests have agreed in showing the vast majority of them detrimental to the organism in its job of surviving and reproducing -- good ones are so rare we can consider them all bad." H.J. Mueller, Bulletin of the Atomic Scientists 11:331. . Anyway, mutations are isolated, random, events that do not build on one another like Legos, and certainly have no ability to create totally new DNA as, for ex., would be needed to turn a leg into a wing. . As for natural selection, it does not lead to evolution, either. What does NS select from? What is already in the genome. It shuffles pre existing information or may cause a loss of information, not the new info you would need to turn a fin into, say, a foot. That is why no matter what it selects from in a fish or bird or lizard or bacteria or monkey or tree or flower you will still have a fish, bird, lizard, bacteria, etc. . But, if you can, give data - not just theories presented as facts in the conveniently invisible past - that a Life Form A turned into Life Form B as the result of NS. In other words show that a species in any genus went to the next level in the Animal Kingdom (ditto for plants) to become a new Family. There are trillions of life forms on this planet. We're told it happened in the unverifiable past, over and over and over. . Why don't we see any species in any genus transitioning to become a member of a new animal or plant family today? . If there is no evidence that any life form's descendants transitioned to become a different family than its ancestors, then there is no evidence for evolution. It's just that simple. But feel free to cite data revealing any such evidence if you can. . Bowler, Peter J., Review of In Search of Deep Time by Henry Gee (Free Press, 1999), American Scientist (vol. 88, March/April 2000), p. 169. "We cannot identify ancestors or 'missing links,' and we cannot devise testable theories to explain how particular episodes of evolution came about. Gee is adamant that all the popular stories about how the first amphibians conquered the dry land, how the birds developed wings and feathers for flying, how the dinosaurs went extinct, and how humans evolved from apes are just products of our imagination, driven by prejudices and preconceptions." . "There are only two possibilities as to how life arose. One is spontaneous generation arising to evolution; the other is a supernatural creative act of God. There is no third possibility. Spontaneous generation, that life arose from non-living matter was scientifically disproved 120 years ago by Louis Pasteur and others. That leaves us with the only possible conclusion that life arose as a supernatural creative act of God. I will not accept that philosophically because I do not want to believe in God. Therefore, I choose to believe in that which I know is scientifically impossible; spontaneous generation arising to evolution." (Nobel Prize winner Wald, George, "Innovation and Biology," Scientific American, Vol. 199, Sept. 1958, p. 100) . "The pathetic thing about it is that many scientists are trying to prove the doctrine of evolution, which no science can do." (Dr. Robert A. Milikan, physicist and Nobel Prize winner, speech before the American Chemical Society.) . "Hypothesis [evolution] based on no evidence and irreconcilable with the facts....These classical evolutionary theories are a gross over-simplification of an immensely complex and intricate mass of facts, and it amazes me that they are swallowed so uncritically and readily, and for such a long time, by so many scientists without a murmur of protest." (Sir Ernst Chan, Nobel Prize winner for developing penicillin) . On this webpage you can see Nobel Prize winning scientists, other secular scientists - including some world famous evolutionists - admitting there is no evidence for evolution. You can see them calling evolution a kind of religion, something that leads to "anti knowledge", etc. Notice how many of these secular scientists acknowledge evidence for a Creator. freerepublic.com/focus/f-bloggers/1435562/posts . Expelled: No Intelligence Allowed shows the politics of Neo Darwinism which harasses and expels those in academia and the media who even hint that there MIGHT be evidence for a Creator. ruclips.net/video/4HErmp5Pzqw/видео.html . As a former atheist and evolution believer, I once had no idea what was outside the box of what I had been told over and over since grade school . Anyone reading this: You are not an ape update. You were created in the very image and likeness of the Creator. He is your Father and loves you and wants you to know Him, and love Him too. Why trade in those fantastic truths for a bunch of mumbo jumbo pseudo science that even secular scientists can't get consensus on? Rhetorical Q.
I don't agree with the evolution theory (I'm watching this video to make a presentation to refute the idea), but I will say this video is well made and well explained. It covered all the information I needed. Excellent job :
Hi there. I love this video and the Cal Academy, but I think it is important to remove the part at 5:03 about eye color in humans. Eye color is controlled many genes with many alleles on multiple chromosomes. The example of eye color being controlled by two alleles at one locus is rife throughout middle school and high school textbooks. This example needs to be eliminated from educational materials so this misconception is eradicated and does not continue to persist. I respectfully request that the Academy replace that portion of the video with another example of a trait that is controlled by one gene and two alleles.
No way. It's a very basic overview that covers key concepts you need to know going into a class or section of a class on population genetics and basic evolutionary theory. He actually left a /lot/ out. I'd know.
On the last pair of chromosomes XX is for female and Xy is for male. When he showed the 46 chromosomes he only showed the male. (I'm just mentioning this for the younger audience who aren't familiar with chromosomes yet.)
Hi! I liked the vid! I've been trying to find for a RUclips vid like yours that really informs the topics in this RUclips vid. 🙌 👩⚕️ The part at 1:15 is my favorite. Your explanation totally is like the content of this new health enthusiast Doctor Ethan! His explanations are for sure informative and I learned a lot for school. He is a new med student. You should see his RUclips out and give the health enthusiast a like! ➡️ #DoctorEthanMedLife
Genetic diversity in one ethnic group. 3 anthropological types are clearly visible: northern Europeans, southern Europeans, Eastern Europeans (with an Asian admixture) Real Russia/Provincial Russia. Rostov on Don region, Donskoy small town, population: 13,648 - ethnic russians 91%: 30% Don сossacks (russian subethnic group - semi-militarized people for military and border services in Russian Empire). Graduation high school ceremony and concert. *olnNpJeKxjQ* PS: Cossacks - Originally Wild Nomads who were employed for military border service in the Muscovite Kingdom. The ancient tradition of the Cossacks is to steal the most beautiful girls in Poland, Iran (Persia) and Turkey, etc (from Military Companies). The distinctive character trait: the unquestioning subordination of the younger to the elders and iron discipline, military democracy(absence of serfdom)...
uhhhh, too much info. I don't get it. It has no meaning. IT MUST HAVE A MEANING, OR ELSE. Therefore I must create an alternative story that is easy to understand. Except, it is made up and not true...
Skip to 7:07 if you're just here for a reminder of gene flow. You're ideas of the term are probably right though considering the definition is in the name.
the best video i've seen so far explaining this stuff. wish you could stuff more information into this!
The topics of genetic variation, gene flow, and the emergence of new species are fundamental concepts in evolutionary biology, providing insight into the mechanisms that drive biodiversity and shape the natural world. These processes, often interrelated, play crucial roles in the adaptation and diversification of organisms over time.
Genetic Variation:
Genetic variation refers to the differences in DNA sequences among individuals within a population. This variation is the raw material upon which natural selection acts, enabling populations to adapt to changing environments. Genetic diversity can arise from mutations, recombination during sexual reproduction, and other genetic processes. Without genetic variation, evolution cannot occur because there would be no new traits for natural selection to act upon.
This variation is crucial for the survival of species, as it provides the adaptability needed to thrive in different environments or to resist diseases and other challenges. For example, populations with high genetic diversity are more likely to survive changes in climate or new pathogens, while populations with low diversity may face higher risks of extinction due to their lack of adaptive potential.
Gene Flow:
Gene flow, also known as genetic migration, is the transfer of genetic material between populations of the same species. It occurs when individuals from different populations interbreed, introducing new genetic material into the gene pool. Gene flow can increase genetic diversity within a population, reduce genetic differences between populations, and prevent the buildup of genetic divergence that might lead to speciation.
Gene flow is essential in maintaining the genetic health of populations by counteracting the negative effects of inbreeding, such as the expression of harmful recessive traits. However, it can also limit the formation of new species because it homogenizes populations and reduces the likelihood of genetic divergence.
On the other hand, gene flow can also introduce new traits into a population, which can help drive adaptation. For instance, if individuals from a population living in a resource-rich environment mate with individuals from a population living in a harsher environment, the offspring may inherit a combination of traits that allow them to survive in more challenging conditions.
New Species and Speciation:
Speciation is the process by which new species arise, typically as a result of genetic divergence between populations. When populations of the same species become isolated-geographically, ecologically, or behaviorally-they can begin to accumulate genetic differences over time, leading to the emergence of new species. This divergence can be driven by mutations, natural selection, genetic drift, and a lack of gene flow between the isolated populations.
There are two primary forms of speciation:
1. Allopatric Speciation: Occurs when populations are geographically isolated, preventing gene flow. Over time, genetic differences accumulate between the populations, leading to reproductive isolation and the formation of new species.
2. Sympatric Speciation: Happens without geographic isolation. Instead, speciation occurs within a single population due to ecological or behavioral differences, such as shifts in habitat use or mating preferences. This can lead to reproductive isolation, even in the absence of physical barriers.
The genetic and ecological factors that drive speciation are complex and depend on many variables, including mutation rates, environmental pressures, and social behaviors within populations. Gene flow, in this context, can either hinder or facilitate speciation, depending on the degree of genetic divergence and the presence of reproductive barriers.
Interaction Between Genetic Variation, Gene Flow, and Speciation:
The interplay between genetic variation, gene flow, and speciation is key to understanding how new species arise and how biodiversity is maintained. Genetic variation provides the raw material for adaptation, while gene flow can either promote or impede the differentiation of populations. When gene flow is limited or absent, genetic divergence increases, setting the stage for speciation.
On the other hand, if gene flow is high between populations, it can slow or prevent speciation by mixing genetic material, preventing the accumulation of differences necessary for the development of reproductive isolation. In cases of hybridization, where individuals from different species interbreed, gene flow can sometimes lead to the formation of new species, either through the establishment of hybrids that have distinct characteristics or through the process of polyploidy (especially in plants).
Conclusion:
The processes of genetic variation, gene flow, and speciation are intertwined, and their interactions are fundamental to the evolutionary processes that drive the diversity of life. Genetic variation provides the foundation for evolutionary change, gene flow acts as a force of both homogenization and potential adaptation, and speciation is the ultimate outcome of these forces when populations diverge sufficiently to become distinct species. Understanding these processes is crucial not only for studying evolutionary biology but also for applying this knowledge to fields like conservation biology, agriculture, and medicine, where maintaining genetic diversity and preventing the loss of species are of paramount importance.
It's really one of the best lecture ever
helps me so much with my exams thank you
you provide unnecessary information. but above all your video is the best.
Very easy to understand! and great illustrations. this helped me a lot. I'm in my first year of my bio major.
Best and most understandable video so far
well explained in a simple way, absolutely loved it.
this video was very helpful in understanding every aspect of each subtopic amazing job
you just saved my hnrs bio grade
you cleared all my doubts on evolution
This is so helpful thank you😭
Great video, helped me out a lot for my test.
this help me so much with my open house!! Thx u
Thanks for valuable information in a simple way
is this video also about animal population genetics
What are the difference between Intra-individuals (Qi) and inter-individuals intra-population genetic variance and what could it tell us?
Thank you science teacher
Please can you teach chapter environment class 10
Very clear, very nice illustrated, great movie on this (not so easy) subject!
Thank you so much..This lecture is Excellent 💕👍👍
Easy to understand.. excellent
Please Make more Such educational videos.. Thanks
Great video and nice job! Thank you!
I do have a question regarding the "randomness" -- when we look at how the cell reproduce,how DNA replicates and how the stars and atoms move, we really don't see too much randomness there. What is your definition / examples of randomness? Many Thanks!
thanks for the amazing vid
Absolutely understandable
If 2 human populations were separated without the ability to interbreed, with very different environments, how long would it take for differences to develop so that they could not interbreed if they met?
Great lecture 💥💕
Randomness is when mutations or gene restrictions occur over a long period of time.
Let's look at what some secular scientists have had to say that disagrees with evolutionism.
We are told that beneficial mutations are an essential mechanism for evolution to occur, but H. J. Muller, who won a Nobel Prize for his work on mutations, said....
"It is entirely in line with the accidental nature of mutations that extensive tests have agreed in showing the vast majority of them detrimental to the organism in its job of surviving and reproducing -- good ones are so rare we can consider them all bad." H.J. Mueller, Bulletin of the Atomic Scientists 11:331.
.
Anyway, mutations are isolated, random, events that do not build on one another like Legos, and certainly have no ability to create totally new DNA as, for ex., would be needed to turn a leg into a wing.
.
As for natural selection, it does not lead to evolution, either. What does NS select from? What is already in the genome. It shuffles pre existing information or may cause a loss of information, not the new info you would need to turn a fin into, say, a foot. That is why no matter what it selects from in a fish or bird or lizard or bacteria or monkey or tree or flower you will still have a fish, bird, lizard, bacteria, etc.
.
But, if you can, give data - not just theories presented as facts in the conveniently invisible past - that a Life Form A turned into Life Form B as the result of NS. In other words show that a species in any genus went to the next level in the Animal Kingdom (ditto for plants) to become a new Family. There are trillions of life forms on this planet. We're told it happened in the unverifiable past, over and over and over.
.
Why don't we see any species in any genus transitioning to become a member of a new animal or plant family today?
.
If there is no evidence that any life form's descendants transitioned to become a different family than its ancestors, then there is no evidence for evolution. It's just that simple. But feel free to cite data revealing any such evidence if you can.
.
Bowler, Peter J., Review of In Search of Deep Time by Henry Gee (Free Press, 1999), American Scientist (vol. 88, March/April 2000), p. 169.
"We cannot identify ancestors or 'missing links,' and we cannot devise testable theories to explain how particular episodes of evolution came about. Gee is adamant that all the popular stories about how the first amphibians conquered the dry land, how the birds developed wings and feathers for flying, how the dinosaurs went extinct, and how humans evolved from apes are just products of our imagination, driven by prejudices and preconceptions."
.
"There are only two possibilities as to how life arose. One is spontaneous generation arising to evolution; the other is a supernatural creative act of God. There is no third possibility. Spontaneous generation, that life arose from non-living matter was scientifically disproved 120 years ago by Louis Pasteur and others. That leaves us with the only possible conclusion that life arose as a supernatural creative act of God. I will not accept that philosophically because I do not want to believe in God. Therefore, I choose to believe in that which I know is scientifically impossible; spontaneous generation arising to evolution." (Nobel Prize winner Wald, George, "Innovation and Biology," Scientific American, Vol. 199, Sept. 1958, p. 100)
.
"The pathetic thing about it is that many scientists are trying to prove the doctrine of evolution, which no science can do." (Dr. Robert A. Milikan, physicist and Nobel Prize winner, speech before the American Chemical Society.)
.
"Hypothesis [evolution] based on no evidence and irreconcilable with the facts....These classical evolutionary theories are a gross over-simplification of an immensely complex and intricate mass of facts, and it amazes me that they are swallowed so uncritically and readily, and for such a long time, by so many scientists without a murmur of protest."
(Sir Ernst Chan, Nobel Prize winner for developing penicillin)
.
On this webpage you can see Nobel Prize winning scientists, other secular scientists - including some world famous evolutionists - admitting there is no evidence for evolution. You can see them calling evolution a kind of religion, something that leads to "anti knowledge", etc. Notice how many of these secular scientists acknowledge evidence for a Creator.
freerepublic.com/focus/f-bloggers/1435562/posts
.
Expelled: No Intelligence Allowed shows the politics of Neo Darwinism which harasses and expels those in academia and the media who even hint that there MIGHT be evidence for a Creator.
ruclips.net/video/4HErmp5Pzqw/видео.html
.
As a former atheist and evolution believer, I once had no idea what was outside the box of what I had been told over and over since grade school
.
Anyone reading this: You are not an ape update. You were created in the very image and likeness of the Creator. He is your Father and loves you and wants you to know Him, and love Him too. Why trade in those fantastic truths for a bunch of mumbo jumbo pseudo science that even secular scientists can't get consensus on? Rhetorical Q.
Wow so much info I can't...
It really helpful may God bless you
I don't agree with the evolution theory (I'm watching this video to make a presentation to refute the idea), but I will say this video is well made and well explained. It covered all the information I needed. Excellent job :
hi im doing a literature review about genetic variation, can you help me find relevant reading for this topic?
damn, hope it went well
great video!
I really like the video
Really useful thank you
Best one 💖
Hi there. I love this video and the Cal Academy, but I think it is important to remove the part at 5:03 about eye color in humans. Eye color is controlled many genes with many alleles on multiple chromosomes. The example of eye color being controlled by two alleles at one locus is rife throughout middle school and high school textbooks. This example needs to be eliminated from educational materials so this misconception is eradicated and does not continue to persist. I respectfully request that the Academy replace that portion of the video with another example of a trait that is controlled by one gene and two alleles.
Video unclear my head is in a washing machine
I hope your toes get better
Best of the best!
im watching this from khan academy
Skip to 7:18 to see enormous fish delete Central America in a bizarre mating ritual!
Skip to 8:16 to see the egg on my face
to much info in one vide -____-
too
No way. It's a very basic overview that covers key concepts you need to know going into a class or section of a class on population genetics and basic evolutionary theory. He actually left a /lot/ out. I'd know.
too much unintelligence in one comment
On the last pair of chromosomes XX is for female and Xy is for male.
When he showed the 46 chromosomes he only showed the male.
(I'm just mentioning this for the younger audience who aren't familiar with chromosomes yet.)
5:40
nice
Hi! I liked the vid! I've been trying to find for a RUclips vid like yours that really informs the topics in this RUclips vid. 🙌 👩⚕️ The part at 1:15 is my favorite. Your explanation totally is like the content of this new health enthusiast Doctor Ethan! His explanations are for sure informative and I learned a lot for school. He is a new med student.
You should see his RUclips out and give the health enthusiast a like! ➡️ #DoctorEthanMedLife
Lovely
Jeff Goldblum? Is that you?
Decent.
Hand lines are genetic
Best
Nature is harsh 😨
why this guy sound like Jeff Goldblum :|
I was literally thinking that...
ALLAHU AKBAAAR!
LOLWTFBBQz N. Nnnn
Elham
LoL i was just kidding..
Okay I'll delete my comment..
So gene flow supports interracial marriage?
Genetic diversity in one ethnic group. 3 anthropological types are clearly visible: northern Europeans, southern Europeans, Eastern Europeans (with an Asian admixture)
Real Russia/Provincial Russia. Rostov on Don region, Donskoy small town, population: 13,648 - ethnic russians 91%: 30% Don сossacks (russian subethnic group - semi-militarized people for military and border services in Russian Empire).
Graduation high school ceremony and concert. *olnNpJeKxjQ*
PS: Cossacks - Originally Wild Nomads who were employed for military border service in the Muscovite Kingdom. The ancient tradition of the Cossacks is to steal the most beautiful girls in Poland, Iran (Persia) and Turkey, etc (from Military Companies). The distinctive character trait: the unquestioning subordination of the younger to the elders and iron discipline, military democracy(absence of serfdom)...
who else got lab in an hour
survival of the fitter ha
who remember trump in this video hhhhhhhhhhhhhhhhhhhhhh
OOF??
How many indians?
uhhhh, too much info. I don't get it. It has no meaning. IT MUST HAVE A MEANING, OR ELSE. Therefore I must create an alternative story that is easy to understand. Except, it is made up and not true...