Using Gradients To Explain Long-Term Changes

[Gavinchi]

As an aspiring Biology teacher, I thought of a way to express how organisms evolve after a long period of time - never spontaneously transitioning into a new species. I've seen that it's hard for people to comprehend

long intervals of time and change. There is also a massive misunderstanding in how evolution works when creationists point to "missing links" in the evolutionary tree. The only way we wouldn't have missing links is if every organism fossilized (If using the gradient to explain this, we'd state that we would need to find every incredibly thin pixel layer of the gradient). I know evolution can't be explained so easily but I thought it would be easily understood by people who have a difficult time grasping long-term transitions.

What do you think? What would make it better? Does this method of explanation already exist in the scientific community?

[Bender]

I think it is important to note that the gradient isn't constant: there are periods with little evolution and periods more rapid evolution, depending on a variety of factors (including random luck). During "high gradient" periods, you'll have a high probability of "missing links", because the sample rate is not high enough to catch the small details.

[Gavinchi]

I think it is important to note that the gradient isn't constant: there are periods with little evolution and periods more rapid evolution, depending on a variety of factors (including random luck). During "high gradient" periods, you'll have a high probability of "missing links", because the sample rate is not high enough to catch the small details.

Right, that's true. There are a lot of complexities of evolution the gradient couldn't describe but I thought it would be a nice way to show disputers of evolutionary theory how an organism never abruptly shifts into a descendent with noticeable differences.

[Bender]

If you happen to find one that is willing to listen ... .

[Gavinchi]

If you happen to find one that is willing to listen ... .

 

Oh yeah... I forgot that I had to climb over that wall first. Haha, I should know better - having watched Richard Dawkins himself having so much trouble convincing people to look at the facts.

[Arete]

The basic premise of the argument that "organisms only evolve into like organisms, not completely dissimilar organisms - therefore evolution is unproven/belief/etc" is false.

 

The theory of evolution never proposes that organisms "turn into" other organisms - the claim of evolutionary theory is that if you trace the evolutionary history of organisms back far enough, their genealogies will coalesce on a common ancestor. There is no claim or expectation that organisms can evolve across vast evolutionary spaces spontaneously, and if they actually did, our current understanding of evolutionary theory would need considerable revision.

 

An example one might find more comprehensible might be the example of cousins: You and you cousins share a common ancestor in your grandparents. The assumption of shared ancestry does not predict that you can turn into your cousin, or give birth to their children. The evidence of common ancestry is demonstrated by tracing your genetic and/or phenotypic genealogy back to your grandparents - which is how evolutionary biologists trace the genealogies of organisms, only they go much farther back than two generations.

 

Now, imagine that you traced your ancestry back 10 generations to your great, great, great, great, great, great, great, great grandparents. Now imagine you trace a different branch of the genealogy back to a family at the present. This family might be very different to you - live in a different country, speak a different language, have different colored hair, or skin tones or facial features from your family due to the different families that have been involved in their family tree compared to yours.

 

Now the creationist claim is effectively that because this family can't give birth to someone from your family, your shared ancestry is disproven, However we know that you share an ancestor from your family tree, and it's not disproven by the unreasonable expectation that you would give birth to each other's babies. Similarly, if a creationist says, for e.g. that no one has seen a bacteria turn into an elephant means there is no proof for the tree of life, they are making a flawed, and ultimately silly claim.

Edited March 20, 2017 by Arete

[Gavinchi]

The basic premise of the argument that "organisms only evolve into like organisms, not completely dissimilar organisms - therefore evolution is unproven/belief/etc" is false.

 

The theory of evolution never proposes that organisms "turn into" other organisms - the claim of evolutionary theory is that if you trace the evolutionary history of organisms back far enough, their genealogies will coalesce on a common ancestor. There is no claim or expectation that organisms can evolve across vast evolutionary spaces spontaneously, and if they actually did, our current understanding of evolutionary theory would need considerable revision.

 

An example one might find more comprehensible might be the example of cousins: You and you cousins share a common ancestor in your grandparents. The assumption of shared ancestry does not predict that you can turn into your cousin, or give birth to their children. The evidence of common ancestry is demonstrated by tracing your genetic and/or phenotypic genealogy back to your grandparents - which is how evolutionary biologists trace the genealogies of organisms, only they go much farther back than two generations.

 

Now, imagine that you traced your ancestry back 10 generations to your great, great, great, great, great, great, great, great grandparents. Now imagine you trace a different branch of the genealogy back to a family at the present. This family might be very different to you - live in a different country, speak a different language, have different colored hair, or skin tones or facial features from your family due to the different families that have been involved in their family tree compared to yours.

 

Now the creationist claim is effectively that because this family can't give birth to someone from your family, your shared ancestry is disproven, However we know that you share an ancestor from your family tree, and it's not disproven by the unreasonable expectation that you would give birth to each other's babies. Similarly, if a creationist says, for e.g. that no one has seen a bacteria turn into an elephant means there is no proof for the tree of life, they are making a flawed, and ultimately silly claim.

 

 

I agree with you completely! I was also becoming extremely frustrated when looking through my little sister-in-law's "science" textbook to find that it was a scientific creationism publication (She's homeschooled). I sifted through the pages to find that the briefly addressed evolution section just used the flawed "missing link" argument...

[Argent]

This is a similar concept to the one you have presented. It has been around for a few years.

[Gavinchi]

This is a similar concept to the one you have presented. It has been around for a few years.

 

Okay, cool! It's interesting to see that it's been thought of before. Thank you!