full transcript
From the Ted Talk by Alex Gendler: Myths and misconceptions about evolution
Unscramble the Blue Letters
Myths and misconceptions about eutlvoion. Let's talk about evolution. You've probably heard that some people consider it controversial, even though most scientists don't. But even if you aren't one of those plpeoe and you think you have a pretty good understanding of evolution, chances are you still believe some things about it that aren't entirely right, things like, "Evolution is organisms adapting to their environment." This was an eiearlr, now discredited, theory of evolution. Almost 60 years before Darwin pbsuhelid his book, Jean-Baptiste Lamarck proposed that curearets evolve by developing certain traits over their lifetimes and then passing those on to their offspring. For example, he thought that because giraffes snpet their lives sihrtnetcg to reach laeves on higher barhecns, their children would be born with longer necks. But we know now that's not how genetic inheritance works. In fact, individual organisms don't evolve at all. Instead, random genetic mutations cause some gefirfas to be born with longer necks, and that gives them a better chance to survive than the ones who weren't so lkcuy, which brings us to "survival of the fittest". This makes it sound like evolution always favors the biggest, snsrgetot, or fastest creatures, which is not really the case. For one thing, evolutionary fitness is just a matter of how well-suited they are to their current environment. If all the tall teers suddenly died out and only short grass was left, all those long-necked giraffes would be at a dnvaitdaagse. Secondly, survival is not how evolution occurs, reproduction is. And the world if full of creatures like the male anglerfish, which is so small and ill-suited for survival at birth that it has to quickly find a mate before it dies. But at least we can say that if an organism dies without reproducing, it's evolutionarily useless, right? Wrong! Remember, nruatal silteeocn happens not at the organism level, but at the genetic level, and the same gene that extsis in one organism will also esxit in its relatives. So, a gene that makes an animal altruistically sacrifice itself to help the survival and future reproduction of its siblings or cousins, can become more widespread than one that is solely concerned with self-preservation. Anything that lets more copies of the gene pass on to the next generation will serve its purpose, except evolutionary purpose. One of the most difficult things to keep in mind about evolution is that when we say things like, "Genes want to make more ceoips of themselves," or even, "natural selection," we're actually using metaphors. A gene doesn't want anything, and there's no outside mechanism that selects which genes are best to preserve. All that happens is that random genetic maionttus cause the organisms cnyarirg them to bvahee or develop in different ways. Some of those ways result in more copies of the mutated gene being passed on, and so forth. Nor is there any pemenrriteedd plan progressing towards an ideal form. It's not ideal for the human eye to have a blind spot where the optic nerve eitxs the retina, but that's how it developed, starting from a simlpe photoreceptor cell. In retrospect, it would have been much more advantageous for humans to cvare nunrteits and vitamins rather than just calories. But over the meinlila,
Open Cloze
Myths and misconceptions about _________. Let's talk about evolution. You've probably heard that some people consider it controversial, even though most scientists don't. But even if you aren't one of those ______ and you think you have a pretty good understanding of evolution, chances are you still believe some things about it that aren't entirely right, things like, "Evolution is organisms adapting to their environment." This was an _______, now discredited, theory of evolution. Almost 60 years before Darwin _________ his book, Jean-Baptiste Lamarck proposed that _________ evolve by developing certain traits over their lifetimes and then passing those on to their offspring. For example, he thought that because giraffes _____ their lives __________ to reach ______ on higher ________, their children would be born with longer necks. But we know now that's not how genetic inheritance works. In fact, individual organisms don't evolve at all. Instead, random genetic mutations cause some ________ to be born with longer necks, and that gives them a better chance to survive than the ones who weren't so _____, which brings us to "survival of the fittest". This makes it sound like evolution always favors the biggest, _________, or fastest creatures, which is not really the case. For one thing, evolutionary fitness is just a matter of how well-suited they are to their current environment. If all the tall _____ suddenly died out and only short grass was left, all those long-necked giraffes would be at a ____________. Secondly, survival is not how evolution occurs, reproduction is. And the world if full of creatures like the male anglerfish, which is so small and ill-suited for survival at birth that it has to quickly find a mate before it dies. But at least we can say that if an organism dies without reproducing, it's evolutionarily useless, right? Wrong! Remember, _______ _________ happens not at the organism level, but at the genetic level, and the same gene that ______ in one organism will also _____ in its relatives. So, a gene that makes an animal altruistically sacrifice itself to help the survival and future reproduction of its siblings or cousins, can become more widespread than one that is solely concerned with self-preservation. Anything that lets more copies of the gene pass on to the next generation will serve its purpose, except evolutionary purpose. One of the most difficult things to keep in mind about evolution is that when we say things like, "Genes want to make more ______ of themselves," or even, "natural selection," we're actually using metaphors. A gene doesn't want anything, and there's no outside mechanism that selects which genes are best to preserve. All that happens is that random genetic _________ cause the organisms ________ them to ______ or develop in different ways. Some of those ways result in more copies of the mutated gene being passed on, and so forth. Nor is there any _____________ plan progressing towards an ideal form. It's not ideal for the human eye to have a blind spot where the optic nerve _____ the retina, but that's how it developed, starting from a ______ photoreceptor cell. In retrospect, it would have been much more advantageous for humans to _____ _________ and vitamins rather than just calories. But over the ________,
Solution
- people
- evolution
- exist
- selection
- behave
- carrying
- earlier
- mutations
- creatures
- published
- strongest
- disadvantage
- natural
- trees
- stretching
- giraffes
- millenia
- crave
- simple
- nutrients
- branches
- exists
- spent
- lucky
- leaves
- copies
- exits
- predetermined
Original Text
Myths and misconceptions about evolution. Let's talk about evolution. You've probably heard that some people consider it controversial, even though most scientists don't. But even if you aren't one of those people and you think you have a pretty good understanding of evolution, chances are you still believe some things about it that aren't entirely right, things like, "Evolution is organisms adapting to their environment." This was an earlier, now discredited, theory of evolution. Almost 60 years before Darwin published his book, Jean-Baptiste Lamarck proposed that creatures evolve by developing certain traits over their lifetimes and then passing those on to their offspring. For example, he thought that because giraffes spent their lives stretching to reach leaves on higher branches, their children would be born with longer necks. But we know now that's not how genetic inheritance works. In fact, individual organisms don't evolve at all. Instead, random genetic mutations cause some giraffes to be born with longer necks, and that gives them a better chance to survive than the ones who weren't so lucky, which brings us to "survival of the fittest". This makes it sound like evolution always favors the biggest, strongest, or fastest creatures, which is not really the case. For one thing, evolutionary fitness is just a matter of how well-suited they are to their current environment. If all the tall trees suddenly died out and only short grass was left, all those long-necked giraffes would be at a disadvantage. Secondly, survival is not how evolution occurs, reproduction is. And the world if full of creatures like the male anglerfish, which is so small and ill-suited for survival at birth that it has to quickly find a mate before it dies. But at least we can say that if an organism dies without reproducing, it's evolutionarily useless, right? Wrong! Remember, natural selection happens not at the organism level, but at the genetic level, and the same gene that exists in one organism will also exist in its relatives. So, a gene that makes an animal altruistically sacrifice itself to help the survival and future reproduction of its siblings or cousins, can become more widespread than one that is solely concerned with self-preservation. Anything that lets more copies of the gene pass on to the next generation will serve its purpose, except evolutionary purpose. One of the most difficult things to keep in mind about evolution is that when we say things like, "Genes want to make more copies of themselves," or even, "natural selection," we're actually using metaphors. A gene doesn't want anything, and there's no outside mechanism that selects which genes are best to preserve. All that happens is that random genetic mutations cause the organisms carrying them to behave or develop in different ways. Some of those ways result in more copies of the mutated gene being passed on, and so forth. Nor is there any predetermined plan progressing towards an ideal form. It's not ideal for the human eye to have a blind spot where the optic nerve exits the retina, but that's how it developed, starting from a simple photoreceptor cell. In retrospect, it would have been much more advantageous for humans to crave nutrients and vitamins rather than just calories. But over the millenia,
Frequently Occurring Word Combinations
ngrams of length 2
| collocation |
frequency |
| random genetic |
2 |
| genetic mutations |
2 |
ngrams of length 3
| collocation |
frequency |
| random genetic mutations |
2 |
Important Words
- adapting
- advantageous
- altruistically
- anglerfish
- animal
- behave
- biggest
- birth
- blind
- book
- born
- branches
- brings
- calories
- carrying
- case
- cell
- chance
- chances
- children
- concerned
- controversial
- copies
- cousins
- crave
- creatures
- current
- darwin
- develop
- developed
- developing
- died
- dies
- difficult
- disadvantage
- discredited
- earlier
- environment
- evolution
- evolutionarily
- evolutionary
- evolve
- exist
- exists
- exits
- eye
- fact
- fastest
- favors
- find
- fitness
- form
- full
- future
- gene
- generation
- genes
- genetic
- giraffes
- good
- grass
- heard
- higher
- human
- humans
- ideal
- individual
- inheritance
- lamarck
- leaves
- left
- lets
- level
- lifetimes
- lives
- longer
- lucky
- male
- mate
- matter
- mechanism
- metaphors
- millenia
- mind
- misconceptions
- mutated
- mutations
- myths
- natural
- necks
- nerve
- nutrients
- occurs
- offspring
- optic
- organism
- organisms
- pass
- passed
- passing
- people
- photoreceptor
- plan
- predetermined
- preserve
- pretty
- progressing
- proposed
- published
- purpose
- quickly
- random
- reach
- relatives
- remember
- reproducing
- reproduction
- result
- retina
- retrospect
- sacrifice
- scientists
- selection
- selects
- serve
- short
- siblings
- simple
- small
- solely
- sound
- spent
- spot
- starting
- stretching
- strongest
- suddenly
- survival
- survive
- talk
- tall
- theory
- thought
- traits
- trees
- understanding
- useless
- vitamins
- ways
- widespread
- works
- world
- years