Darwin’s theory was that species are the result of natural selection acting on the variation of phenotypes in a species. Finches might have beaks from skinny to strong, but if thick shelled seeds are the most available food, then over time there will be a species of finches with strong beaks, and the finches with skinny beaks might disappear. Darwin argued that based on how all life appeared to be related in how their bodies were structured, it’s conceivable that natural selection acting on variation in a species could have produced all of the variety of life on Earth.
Lamarck held with an older idea, that it was the needs of individuals of a species that caused their offspring to change. An animal that needed to constantly stretch its neck to reach higher leaves would have offspring with longer necks, and eventually there’d be giraffes.
So the clear differentiation between Lamarck and Darwin is that Lamarck believed that evolution was the result of individuals striving to survive, while Darwin argued (and had the specimen collection to illustrate it) that evolution was the result of the environment acting on the entire population of a species.
The modern theory of evolution has a lot more information that neither Lamarck nor Darwin had, including genetics, and more recently epigenetics.
Genetics makes variability possible, and it is also what results in selecting for the best characteristics as individuals mix genes and produce offspring.
But epigenetics sounds almost as if Lamarck might have at least had a small point. It turns out that some genes can be turned on or off due to a parent’s environment, and that gene, turned on or off, will be passed along to the offspring. It’s not quite what Lamarck was thinking, but I’m willing to give him a nod.
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Darwin’s theory was that species are the result of natural selection acting on the variation of phenotypes in a species. Finches might have beaks from skinny to strong, but if thick shelled seeds are the most available food, then over time there will be a species of finches with strong beaks, and the finches with skinny beaks might disappear. Darwin argued that based on how all life appeared to be related in how their bodies were structured, it’s conceivable that natural selection acting on variation in a species could have produced all of the variety of life on Earth.
Lamarck held with an older idea, that it was the needs of individuals of a species that caused their offspring to change. An animal that needed to constantly stretch its neck to reach higher leaves would have offspring with longer necks, and eventually there’d be giraffes.
So the clear differentiation between Lamarck and Darwin is that Lamarck believed that evolution was the result of individuals striving to survive, while Darwin argued (and had the specimen collection to illustrate it) that evolution was the result of the environment acting on the entire population of a species.
The modern theory of evolution has a lot more information that neither Lamarck nor Darwin had, including genetics, and more recently epigenetics.
Genetics makes variability possible, and it is also what results in selecting for the best characteristics as individuals mix genes and produce offspring.
But epigenetics sounds almost as if Lamarck might have at least had a small point. It turns out that some genes can be turned on or off due to a parent’s environment, and that gene, turned on or off, will be passed along to the offspring. It’s not quite what Lamarck was thinking, but I’m willing to give him a nod.