yhelothar
Lifer
- Dec 11, 2002
- 18,409
- 39
- 91
Just because you've never taken past 9th grade bio and don't understand evolution, it doean't mean there isn't an answer.
Every species is part of the link. They follow a phylogenic tree. It's true that there are many missing links in the fossil record, but that doesn't mean there are "transitional species," which is straw man argument that is commonly used by creationists.
A good example is giraffes.
The short ones may died out in that one area, but survived fine in another area. Thus you still have that old species of horses in another habitat, and you get giraffes in addition.
Even Pope John Paul II accepted that evolution is one of the laws of nature, and he was infallible at the time. What more do you need to know?
Pope says so!
Pope says so!
I've always thought that it comes from genetic mutations from radiation, damage from chemicals or viruses, mixing of genes etc. I think there are now some new theories that say environment also shapes some hereditary processes.
Jeff7
Lifer
- Jan 4, 2001
- 41,596
- 19
- 81
And taught well. Too many people think that an animal says "I can't find food, I'm going to evolve into something different," and bam, it suddenly has an adaptation that lets it survive better. Evolution has no conscious guidance. It's combinations of random mutations that either help an organism survive, either by slightly increasing its chances of finding food or a mate, or by helping it avoid predators.
Say you have 100 animals. Half are bright red, and thus easy for predators to see. The other half happen to be a slightly different shade of red, one that's less reflective. It's just a random genetic screwup. But out of these animals, the darker ones are more likely to remain unseen by predators. Being alive greatly increases chances of reproducing, and in doing so, this darker mutation is passed on. It's random chance combined with laws of probability, repeated many many times. That which cannot survive until it is able to reproduce is "deemed" ineffective by the process of natural selection, thus its genes are eliminated from the pool. Continue doing this over hundreds upon hundreds of generations, and there will be gradual change in the species' genetic makeup.
I'm bringing popcorn, :beer: and DNA to this thread.
The answer to all of this thread is hidden in this post.
The answer to all of this thread is hidden in this post.
mugs
Lifer
- Apr 29, 2003
- 48,920
- 46
- 91
>Too many people think that an animal says "I can't find food, I'm going to evolve into something different,"
Amusingly, I read a paper a while back about some bacteria that have higher mutation rates when stressed.
Amusingly, I read a paper a while back about some bacteria that have higher mutation rates when stressed.
OK....first of all, the birds are Finches (now approproately called Darwin's Finches). They use their beaks to eat seeds, and not to drink honey from flowers. 
Secondly, thank you to those of you who know what DNA is.
For those of you who are interested in separating yourselves from the monkeys (haha, evolution humor...get it?...monkeys)
DNA is composed of 4 "building blocks" called Adenine, Thymine, Cytosine and Guanine. These are all arranged in a specific order, and each strand of DNA (there are 2) are held together by these bases: A always pairs with T, C with G. Certain proteins "read" areas of this DNA and "make" a "messenger strand" which is then "turned into" protein. Animals are made of protein, and what is not protein was made by proteins (i.e., enzymes are proteins and act as little machines to do all sorts of work in your body). Thus, the body comes from DNA.
(this gets a wee bit hairy...hang in there..you know you wanna) Now, the areas which are "read" from the DNA are called genes. Many signals dictate when genes are turned on, and these can come from the external environment, or the internal cellular environment. Ultimately though, general transcription factors (the proteins which help the "reading") must bind to the DNA before it can be read. They do this at certain specific regions of DNA near genes. If general transcription factors bind to the DNA, then the gene can be "read." BUT, these factors need to be recruited, and there are several different "signalling proteins" which help to do this, and each binds to its own unique site called a cis-regulatory element, which is also near or in the gene. These "signalling proteins" can "enhance" (turn on) or "silence" (turn off) a gene.
One of the newer ideas in evolution is that mutations in these cis-regulatory element sites causes a much greater difference in species changes than the mutation of a gene (which also occurs, don't get me wrong). This is because whole genes can be turned on or off depending on whether or not the cis-regulatory elements can bind their signalling proteins, and the same signalling proteins are used in various areas of an organism and at specific times. Thus, there may be several signalling molecules in "the same place at the same time" and they bind to their specific cis-regulatory elements, turning on and off their own genes. Mutating these elements can cause already existing signalling molecules to bind near new genes and have a different effect. Thus, genes which were turned on may be turned off and vice versa. Depending on when during development this occurs, a miriad of changes to the organism may occur. Granted, most of these could prove fatal, but experiments with fruit fly wing and body color have been most exciting (google Sean B. Carroll or read Endless Forms Most Beautiful).
Many experiments have been done between animals and it has been shown that there exists genes for things which aren't turned "on" and when (for example) molar mesenchyme tissue from a mouse (mouth tissue) is placed under the beak area of a chicken (which has no teeth) a reptile tooth is formed. Thus, the reptile tooth gene was in the chicken, but was not "on" and it needed a "signal" from the mouse tissue (which could have been any number of signalling molecules).
Basically, evolution happens and it is way cool. There is ~ 100 years of research backing up what is defined as a theory only because no one was alive to watch it. It can, however, be observed on the micro level with things such as the AIDS virus (read up on how AIDS medicine works if you don't beleive me) and antibiotic resistance aquiration in bacteria. Addressing other issues, the fossil record is known to be incomplete, and so therefor cannot be used in evidence for or against evolution, however "missing links" are readily being discovered. Addressing those ID peeps...why do we have vesigial organs (and since I'm sure you don't know anything about biology, that means why do we have a residual tail and an appendix if they have no use to us, but do in lower on the phylogenetic tree organisms...which we ALSO mirror in fetal development?) If someone was so intellegent, why would they make something useless?
Secondly, thank you to those of you who know what DNA is.
For those of you who are interested in separating yourselves from the monkeys (haha, evolution humor...get it?...monkeys
)DNA is composed of 4 "building blocks" called Adenine, Thymine, Cytosine and Guanine. These are all arranged in a specific order, and each strand of DNA (there are 2) are held together by these bases: A always pairs with T, C with G. Certain proteins "read" areas of this DNA and "make" a "messenger strand" which is then "turned into" protein. Animals are made of protein, and what is not protein was made by proteins (i.e., enzymes are proteins and act as little machines to do all sorts of work in your body). Thus, the body comes from DNA.
(this gets a wee bit hairy...hang in there..you know you wanna) Now, the areas which are "read" from the DNA are called genes. Many signals dictate when genes are turned on, and these can come from the external environment, or the internal cellular environment. Ultimately though, general transcription factors (the proteins which help the "reading") must bind to the DNA before it can be read. They do this at certain specific regions of DNA near genes. If general transcription factors bind to the DNA, then the gene can be "read." BUT, these factors need to be recruited, and there are several different "signalling proteins" which help to do this, and each binds to its own unique site called a cis-regulatory element, which is also near or in the gene. These "signalling proteins" can "enhance" (turn on) or "silence" (turn off) a gene.
One of the newer ideas in evolution is that mutations in these cis-regulatory element sites causes a much greater difference in species changes than the mutation of a gene (which also occurs, don't get me wrong). This is because whole genes can be turned on or off depending on whether or not the cis-regulatory elements can bind their signalling proteins, and the same signalling proteins are used in various areas of an organism and at specific times. Thus, there may be several signalling molecules in "the same place at the same time" and they bind to their specific cis-regulatory elements, turning on and off their own genes. Mutating these elements can cause already existing signalling molecules to bind near new genes and have a different effect. Thus, genes which were turned on may be turned off and vice versa. Depending on when during development this occurs, a miriad of changes to the organism may occur. Granted, most of these could prove fatal, but experiments with fruit fly wing and body color have been most exciting (google Sean B. Carroll or read Endless Forms Most Beautiful).
Many experiments have been done between animals and it has been shown that there exists genes for things which aren't turned "on" and when (for example) molar mesenchyme tissue from a mouse (mouth tissue) is placed under the beak area of a chicken (which has no teeth) a reptile tooth is formed. Thus, the reptile tooth gene was in the chicken, but was not "on" and it needed a "signal" from the mouse tissue (which could have been any number of signalling molecules).
Basically, evolution happens and it is way cool. There is ~ 100 years of research backing up what is defined as a theory only because no one was alive to watch it. It can, however, be observed on the micro level with things such as the AIDS virus (read up on how AIDS medicine works if you don't beleive me) and antibiotic resistance aquiration in bacteria. Addressing other issues, the fossil record is known to be incomplete, and so therefor cannot be used in evidence for or against evolution, however "missing links" are readily being discovered. Addressing those ID peeps...why do we have vesigial organs (and since I'm sure you don't know anything about biology, that means why do we have a residual tail and an appendix if they have no use to us, but do in lower on the phylogenetic tree organisms...which we ALSO mirror in fetal development?) If someone was so intellegent, why would they make something useless?
yhelothar
Lifer
- Dec 11, 2002
- 18,409
- 39
- 91
Originally posted by: persephone1
OK....first of all, the birds are Finches (now approproately called Darwin's Finches). They use their beaks to eat seeds, and not to drink honey from flowers.
Secondly, thank you to those of you who know what DNA is.
For those of you who are interested in separating yourselves from the monkeys (haha, evolution humor...get it?...monkeys
DNA is composed of 4 "building blocks" called Adenine, Thymine, Cytosine and Guanine. These are all arranged in a specific order, and each strand of DNA (there are 2) are held together by these bases: A always pairs with T, C with G. Certain proteins "read" areas of this DNA and "make" a "messenger strand" which is then "turned into" protein. Animals are made of protein, and what is not protein was made by proteins (i.e., enzymes are proteins and act as little machines to do all sorts of work in your body). Thus, the body comes from DNA.
(this gets a wee bit hairy...hang in there..you know you wanna) Now, the areas which are "read" from the DNA are called genes. Many signals dictate when genes are turned on, and these can come from the external environment, or the internal cellular environment. Ultimately though, general transcription factors (the proteins which help the "reading") must bind to the DNA before it can be read. They do this at certain specific regions of DNA near genes. If general transcription factors bind to the DNA, then the gene can be "read." BUT, these factors need to be recruited, and there are several different "signalling proteins" which help to do this, and each binds to its own unique site called a cis-regulatory element, which is also near or in the gene. These "signalling proteins" can "enhance" (turn on) or "silence" (turn off) a gene.
One of the newer ideas in evolution is that mutations in these cis-regulatory element sites causes a much greater difference in species changes than the mutation of a gene (which also occurs, don't get me wrong). This is because whole genes can be turned on or off depending on whether or not the cis-regulatory elements can bind their signalling proteins, and the same signalling proteins are used in various areas of an organism and at specific times. Thus, there may be several signalling molecules in "the same place at the same time" and they bind to their specific cis-regulatory elements, turning on and off their own genes. Mutating these elements can cause already existing signalling molecules to bind near new genes and have a different effect. Thus, genes which were turned on may be turned off and vice versa. Depending on when during development this occurs, a miriad of changes to the organism may occur. Granted, most of these could prove fatal, but experiments with fruit fly wing and body color have been most exciting (google Sean B. Carroll or read Endless Forms Most Beautiful).
Many experiments have been done between animals and it has been shown that there exists genes for things which aren't turned "on" and when (for example) molar mesenchyme tissue from a mouse (mouth tissue) is placed under the beak area of a chicken (which has no teeth) a reptile tooth is formed. Thus, the reptile tooth gene was in the chicken, but was not "on" and it needed a "signal" from the mouse tissue (which could have been any number of signalling molecules).
Basically, evolution happens and it is way cool. There is ~ 100 years of research backing up what is defined as a theory only because no one was alive to watch it. It can, however, be observed on the micro level with things such as the AIDS virus (read up on how AIDS medicine works if you don't beleive me) and antibiotic resistance aquiration in bacteria. Addressing other issues, the fossil record is known to be incomplete, and so therefor cannot be used in evidence for or against evolution, however "missing links" are readily being discovered. Addressing those ID peeps...why do we have vesigial organs (and since I'm sure you don't know anything about biology, that means why do we have a residual tail and an appendix if they have no use to us, but do in lower on the phylogenetic tree organisms...which we ALSO mirror in fetal development?) If someone was so intellegent, why would they make something useless?
Well said.
We also have gills as a fetus too.. just like tadpoles turning to frogs.
Yes...excellent point about the gills. Oh, and I blush as I realize that I spelled vestigial without a t.
yhelothar
Lifer
- Dec 11, 2002
- 18,409
- 39
- 91
That's more of a cite for refuting creationists claims.
Take an evolutionary biology class.. and evolution will make sense.
I thought it was pointless at first memorizing every single kindom, pylum, class, and order there is. But after, everything fit together like a jigsaw puzzle.
Or The Origin of Species...but (at least so far) it is quite frustrating to read as genetics as we know it today was not known to Darwin. Some of his hereditary postulatings reflect posts in this thread...although he had an excuse, being born in the 19th century and whatnot.
destrekor
Lifer
- Nov 18, 2005
- 28,799
- 359
- 126
basically... like a frog that has 5 legs, is a mutation.... we all know this... and it isn't beneficial to the frog either. but thats why they typically don't get a mate or the gene just doesn't get passed along as its not a vital gene mutation, and sometimes its a fatal mutation anyway as it may limit the ability to survive.
but every now and then there is a mutation that just seems to provide an edge for the creature. like the giraffe example, the longer neck was a freak genetic mutation (in the first place) but it provided an edge for getting food and fared better compared to other giraffes... thus, it passed along its mutated genes.
i got that right.. right?
but every now and then there is a mutation that just seems to provide an edge for the creature. like the giraffe example, the longer neck was a freak genetic mutation (in the first place) but it provided an edge for getting food and fared better compared to other giraffes... thus, it passed along its mutated genes.
i got that right.. right?
TRENDING THREADS
-
Discussion Zen 5 Speculation (EPYC Turin and Strix Point/Granite Ridge - Ryzen 9000)- Started by DisEnchantment
- Replies: 24K
-
Discussion Intel Meteor, Arrow, Lunar & Panther Lakes Discussion Threads
- Started by Tigerick
- Replies: 21K
-
Discussion Intel current and future Lakes & Rapids thread- Started by TheF34RChannel
- Replies: 23K
-
-
Facebook
Twitter