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[Tntnnbltn]

Sex is enjoyable because enjoying sex was a trait that made a species more likely to continue thus individuals that enjoyed engaging in sex were more likely to take off their jeans.

Fixed?

Edit: I hate getting top of the new page with an unsubstantial post. Here's more info about potential evolutionary advantages of homosexuality instead.

Male Homosexuality Can Be Explained Through A Specific Model Of Darwinian Evolution, Study Shows

ScienceDaily (June 18, 2008) — An Italian research team, consisting of Andrea Camperio Ciani and Giovanni Zanzotto at the University of Padova and Paolo Cermelli at the University of Torino, found that the evolutionary origin and maintenance of male homosexuality in human populations could be explained by a model based around the idea of sexually antagonistic selection, in which genetic factors spread in the population by giving a reproductive advantage to one sex while disadvantaging the other.

Male homosexuality is thought to be influenced by psycho-social factors, as well as having a genetic component. This is suggested by the high concordance of sexual orientation in identical twins and the fact that homosexuality is more common in males belonging to the maternal line of male homosexuals. These effects have not been shown for female homosexuality, indicating that these two phenomena may have very different origins and dynamics.

Male homosexuality is difficult to explain under Darwinian evolutionary models, because carriers of genes predisposing towards male homosexuality would be likely to reproduce less than average, suggesting that alleles influencing homosexuality should progressively disappear from a population. This changed when previous work by Camperio Ciani and collaborators, published in 2004, showed that females in the maternal line of male homosexuals were more fertile than average.

Challenged by all these empirical data, the authors of the new study considered a range of different hypotheses for the genetic diffusion of male homosexuality. These included: the genetic maternal effects on sons, the heterozygote advantage (as is found in malaria resistance), and "sexually antagonistic selection." The latter is a particular aspect of Darwinian evolution, in which genetic factors spread in the population by giving a reproductive advantage to one sex while disadvantaging the other. This type of evolution has been previously found in insects, birds, and some mammals, but never in humans.

To discover and clarify the dynamics of the genetic factors for homosexuality, the researchers had to screen a large set of models and exclude them one by one. They concluded that the only possible model was that of sexually antagonistic selection. The other models did not fit the empirical data, either implying that the alleles would become extinct too easily or invade the population, or failing to describe the distribution patterns of male homosexuality and female fecundity observed in the families of homosexuals. Only the model of sexually antagonistic selection involving at least two genes -- at least one of which must be on the X chromosome (inherited in males only through their mother) -- accounted for all the known data.

The results of this model show the interaction of male homosexuality with increased female fecundity within human populations, in a complex dynamic, resulting in the maintenance of male homosexuality at stable and relatively low frequencies, and highlighting the effects of heredity through the maternal line.

These findings provide new insights into male homosexuality in humans. In particular, they promote a focus shift in which homosexuality should not be viewed as a detrimental trait (due to the reduced male fecundity it entails), but, rather, should be considered within the wider evolutionary framework of a characteristic with gender-specific benefits, and which promotes female fecundity. This may well be the evolutionary origin of this genetic trait in human beings.

The possible widespread occurrence of sexually antagonistic characteristics in evolutionary processes, which play their evolutionary game by giving a fecundity benefit to one sex while disadvantaging the other, has only recently begun to be appreciated. This is understood as a key mechanism through which high levels of genetic variation are maintained in biological populations.

Male homosexuality is just the first example of an unknown number of sexually antagonistic traits, which contribute to the maintenance of the natural genetic variability of humans. The new perspectives opened by the models developed for sexually antagonistic selection may also contribute to a better understanding of most genetically-based sexual conflicts, which are, at present, poorly understood in humans.

An unexpected implication of the new models concerns the impact that the sexually antagonistic genetic factors for male homosexuality have on the overall fecundity of a population. The findings suggest that the proportion of male homosexuals may signal a corresponding proportion of females with higher fecundity. Consequently, these factors always contribute, all else being equal, a positive net increase of the fecundity of the whole population, when compared to populations in which such factors are lower or absent. This increase grows as the population baseline fecundity decreases; this means that the genes influencing male homosexuality end up playing the role of a buffer effect on any external factors lowering the overall fecundity of the whole population.

 

[Kinitari]

This term purpose is too easily misunderstood when used in this discussion. I can think of 3 different kinds of 'purposes'

1. A universal purpose - something that would exist without the human mind being around to consider it's existence.

2. A biological/Sociological purpose - something as a people we should be doing. More personal than the above, but still not entirely individual.

3. Individual purpose, speaks for itself, completely personal.

 

[Kano on the Phone]

But his actual (human) example wasn't wrong.

Absolutely, and I could have phrased my argument better. I think there's two arguments going on here, one being that the main purpose of an individual as reproduction and the other as the contribution of an individual to the success of a group, and I got the two mixed in trying to make my point. I think both are true.

I still maintain that the correlation between worker bees and humans who can't reproduce isn't direct, but it is analogous.

 

[danwarb]

And that's a very solid point. I'm not arguing that anyone is useless if they can't reproduce, just that their primary biological drive or purpose (for lack of a better word) is to reproduce.

But they do still have an evolutionary effect. See: kin/group selection.

 

[Mr.Squirrel]

We didn't like evolve from anything. That doesn't make any sense. I mean, how can like, an African American person evolve from a white person? We're different skinned!

:lol pls tell me someone didnt say that

EDIT: OMG THAT WAS AWESOME :lol:lol:lol:lol:lol!!!!

 

[Tntnnbltn]

:lol pls tell me someone didnt say that

Guess you missed the thread.

 

[Kano on the Phone]

But they do still have an evolutionary effect. See: kin/group selection.

That's why I said "solid point" instead of "eat dicks".

 

[ethic]

Foreskin was selected for because it has a fitness advantage, therefor circumcision is wrong.

 

[Kinitari]

That's why I said "solid point" instead of "eat dicks".

I'm just going to come out and say what we've all been thinking.

I need you and Liu Kang Baking A Pie to get into some sort of fight, or argument.

 

[UFRA]

:lol

So when I first visited this thread and it was a couple pages long, it was roughly some religious bashing and debate, as predicted.

I ignore it for a few days, take a peek now and it's on to the discussion of homosexuality.

Oh GAF, never change. :lol

This thread is evolving as we speak.

 

[curls]

Foreskin was selected for because it has a fitness advantage, therefor circumcision is wrong.

Stay away from pandoras box over there.

 

[Kinitari]

:lol

So when I first visited this thread and it was a couple pages long, it was roughly some religious bashing and debate, as predicted.

I ignore it for a few days, take a peek now and it's on to the discussion of homosexuality.

Oh GAF, never change. :lol

This thread is evolving as we speak.

At least people are trying to keep it on topic by mentioning the evolutionary aspects of both religion and homosexuality =p.

 

[Kano on the Phone]

I'm just going to come out and say what we've all been thinking.

I need you and Liu Kang Baking A Pie to get into some sort of fight, or argument.

There isn't any point. He already knows he's a bitch.

 

[UFRA]

At least people are trying to keep it on topic by mentioning the evolutionary aspects of both religion and homosexuality =p.

True. I just always find it interesting how after a couple days, most GAF topics have some shift in the general discussion. It never fails with these big topics.

 

[Always-honest]

:lol

So when I first visited this thread and it was a couple pages long, it was roughly some religious bashing and debate, as predicted.

I ignore it for a few days, take a peek now and it's on to the discussion of homosexuality.

Oh GAF, never change. :lol

This thread is evolving as we speak.

come back in a week and you'll just find images of big female asses

 

[UFRA]

come back in a week and you'll just find images of big female asses

:lol Considering the tendencies of GAF I wouldn't be surprised.

Spoiler

Can't wait to see the female asses.

 

[Kinitari]

I posted the link to the public Google Doc version of the OP (it's the first line in the OP now), if all goes well, I can get people contributing to make this OP substantially better, I'll be doing my own contribution today and tomorrow, if anyone else wants to, please feel free to, and I will update the OP as frequently as possible (after checking carefully through, to make sure there aren't any malicious links or anything) - if it gets shat up, then I'll keep it closed with only a few people allowed to edit.

 

[Zozobra]

Forgive me if these have already been posted, I've subscribed to this thread but haven't had the time to go through it all yet.

Here are some lectures that Dawkins did back in 1991, I believe there are five of them in total at about an hour a piece. Some might find them to be a little dry, but I enjoyed them and think they'll be very informative to people not familiar with evolution:

Ep1: Waking Up in the Universe - Growing Up in the Universe - Richard Dawkins
Ep2: Designed and Designoid Objects - Growing Up in the Universe - Richard Dawkins
Ep3: Climbing Mount Improbable - Growing Up in the Universe - Richard Dawkins
Ep4: The Ultraviolet Garden - Growing Up in the Universe - Richard Dawkins
Ep5: The Genesis of Purpose - Growing Up in the Universe - Richard Dawkins

 

[jaxword]

:lol

So when I first visited this thread and it was a couple pages long, it was roughly some religious bashing and debate, as predicted.

Don't be That Guy. I'm religious and have no problem with evolution. Criticism of religion doesn't mean bashing, and implying and pretending it is just makes us all look bad.

 

[danwarb]

Origins of Multicellularity: All in the Family

One of the most pivotal steps in evolution-the transition from unicellular to multicellular organisms-may not have required as much retooling as commonly believed, found a globe-spanning collaboration of scientists led by researchers at the Salk Institute for Biological Studies and the US Department of Energy's Joint Genome Institute.

A comparison of the genomes of the multicellular algae Volvox carteri and its closest unicellular relative Chlamydomonas reinhardtii revealed that multicellular organisms may have been able to build their more complex molecular machinery largely from the same list of parts that was already available to their unicellular ancestors.

"If you think of proteins in terms of lego bricks Chlamydomonas already had a great lego set," says James Umen, Ph.D., assistant professor in the Plant Molecular and Cellular Biology Laboratory at the Salk Institute. "Volvox didn't have to buy a new one, and instead could experiment with what it had inherited from its ancestor."

Altogether the findings, published in the journal Science, suggest that very limited protein-coding innovation occurred in the Volvox lineage. "We expected that there would be some major differences in genome size, number of genes, or gene families sizes between Volvox and Chlamydomonas," says Umen. "Mostly that turned out not to be the case."

The evolution of multicellularity occurred repeatedly and independently in diverse lineages including animals, plants, fungi, as well as green and red algae. "This transition is one of the great evolutionary events that shaped life on earth," says co-first author Simon E. Prochnik, Ph.D., a Computationial Scientist at the DOE Joint Genome Institute. "It has generated much thought and speculation about what makes multicellular organisms different or more complex than their unicellular ancestors."

In most cases the switch from a solitary existence to a communal one happened so long ago-over 500 million years-that the genetic changes enabling it are very difficult to trace. An interesting exception to the rule are volvocine green algae. For them, the transition to multicellularity happened in a series of small, potentially adaptive changes, and the progressive increase in morphological and developmental complexity can still be seen in contemporary members of the group (see slide show).

Volvox, the most sophisticated member of the lineage, is believed to have evolved from a Chlamydomonas-like ancestor within the last 200 million years, making the two living organisms an appealing model to study the evolutionary changes that brought about multicellularity and cellular differentiation.

To gather data for the comparative genomic analysis, the researchers sequenced the 138 million base pair Volvox genome using a whole genome shotgun strategy. The genome itself is 17% larger than the previously sequenced genome of Chlamydomonas and the sequence divergence between the two is comparable to that between human and chicken.

Despite the modest increase in genome size, the number of predicted proteins turned out to be very similar for the two organisms (14,566 in Volvox vs. 14,516 in Chlamydomonas) and no significant differences could be identified in the repertoires of protein domains or domain combinations. Protein domains are parts of proteins that can evolve, function, and exist independently of the rest of the protein chain.

"This was somewhat unexpected," explains Umen, "since innovation at the domain level was previously thought to play a role in the evolution of multicellularity in the plant and animal lineages."

In contrast to the overall lack of innovation, protein families specific to volvocine algae, such as extracellular matrix proteins, were enriched in Volvox compared to Chlamydomonas. Each mature Volvox colony is composed of numerous flagellated cells similar to Chlamydomonas, which are embedded in the surface of a spheroid of elaborately patterned extracellular matrix (ECM) that is clearly related to the Chlamydomonas cell wall. Maybe not surprisingly, the difference in size and complexity between the Volvox extracellular matrix and Chlamydomonas cell wall is mirrored by a dramatic increase in the number and variety of Volvox genes for two major ECM protein families, pherophorins and VMPs.

Additionally, Umen and his collaborators identified an increase in the number of cyclin D proteins in Volvox, which govern cell division and may be necessary to ensure the complex regulation of cell division during Volvox development. Last but not least, Volvox adapted a few of its existing genes to acquire novel functions. Members of the pherophorin family, for one, not only help build the extracellular matrix; some subtypes evolved into a diffusible hormonal trigger for sexual differentiation.

Volvox carteri:

 

[Naked Snake]

Forgive me if these have already been posted, I've subscribed to this thread but haven't had the time to go through it all yet.

Here are some lectures that Dawkins did back in 1991, I believe there are five of them in total at about an hour a piece. Some might find them to be a little dry, but I enjoyed them and think they'll be very informative to people not familiar with evolution:

Ep1: Waking Up in the Universe - Growing Up in the Universe - Richard Dawkins
Ep2: Designed and Designoid Objects - Growing Up in the Universe - Richard Dawkins
Ep3: Climbing Mount Improbable - Growing Up in the Universe - Richard Dawkins
Ep4: The Ultraviolet Garden - Growing Up in the Universe - Richard Dawkins
Ep5: The Genesis of Purpose - Growing Up in the Universe - Richard Dawkins

I watched these a few months back and really enjoyed them.

 

[JesseZao]

I hate chlamydomonas. Stupid pmp-1 gene I worked with!

 

[Kinitari]

Updated the OP, added most of the links suggested, made a few edits, and fiddled with the general design of the post.


PS. I fucking hate you Mario.

 

[Mgoblue201]

Origins of Multicellularity: All in the Family


Volvox carteri:

I mentioned it in a post a few pages back. I was saying that a lot of evolutionary innovations just seem to be a case of reshuffling the genetic deck.

 

[SolarPowered]

Forgive me if these have already been posted, I've subscribed to this thread but haven't had the time to go through it all yet.

Here are some lectures that Dawkins did back in 1991, I believe there are five of them in total at about an hour a piece. Some might find them to be a little dry, but I enjoyed them and think they'll be very informative to people not familiar with evolution:

Ep1: Waking Up in the Universe - Growing Up in the Universe - Richard Dawkins
Ep2: Designed and Designoid Objects - Growing Up in the Universe - Richard Dawkins
Ep3: Climbing Mount Improbable - Growing Up in the Universe - Richard Dawkins
Ep4: The Ultraviolet Garden - Growing Up in the Universe - Richard Dawkins
Ep5: The Genesis of Purpose - Growing Up in the Universe - Richard Dawkins

I've already watched video one and two. These are an amazing find and I'm surprised that I've never seen them posted on GAF.

The ending for video #1 with that cannonball was pretty epic.:lol

 

[Raist]

i think shit just happened. no purpose at all. we will be gone in no time (give or take a couple of thousand years.

There's no "higher purpose", of course. It's not like mutations deliberately happen or life has its own will or something either. And life most probably happened by accident as well.
However, life (and evolution) as a whole do have a "purpose", which is survival (and thus reproduction). This is why flowers have developed specific patterns, nectar etc, birds have specific songs, etc.

 

[Meesh]

That's not a real answer to my question. Let me rephrase then. What do you think is our purpose and how did you come by this knowledge?

Sorry, I wasnt trying to be a dick. I think our purpose is relative to our beliefs and obviously this is where many disagree. I gather that scientifically we're here mainly to reproduce and carry on the family name. Religiously, man is here to serve (a)god and adhere to his/her principles/morals as read in the bible. I'm not about to elaborate on the beliefs of all religions when talking about our purpose because there are so many different ones...it would be messy. As it is, sometimes my posts are messy so...you know what I'm saying.

However, as far as religion and science not mixing, or religion, the Bible and evolution not mixing I disagree. It's true that by definition creation is basically the act of bringing the universe or our world into existence. So many are caught up in the notion that god made man, the world and all it's inhabitants magically. That he's some magical sky man that just waves his wand...I can't blame people for thinking this way because over zealous evangelicals refuse to consider how we're created and only preach the why.What so many don't realize is that the bible only gives us a distilled order of the events of our creation. It tells us what happened(not how)...but our creation is only the introduction to events pertinent to our salvation. The bible is not a text book about the act of creation but a guide for those who choose to follow Jesus's examples. Why would anyone want to do this? Again, the reasons vary.

Personally I'd go so far as to say that the evidence of evolution dispells the conventional belief system of creation. In fact, religion in general needs to accept the fact that life changes to take on new environments. Creationists need to embrace this line of thinking because(simple example) by logic, Adam and Eve's offspring, or rather Noah's offspring would've had to gradually adapt to the various climates of the earth, and that possibly... segregation brought about physical changes needed to survive in those new environments. I strongly believe...that a wise creator or god would have created life so that it could survive even in the worst circumstances, that it grows as the earth does. The earth has the abillity to heal...the healing process could easily be a part of evolution, just as it does when it's dying. For example disorders or mutations in people these days are rising, such as autism. My son is autistic, I know now that this is more common these days...something like 1 in 90 boys?(don't quote me)Fewer cases in girls. Nobody knows for sure what the trigger is and there are so many degrees of autism, but genetics play a role. Is autism one of those evolutionary negatives or positives that directly reflect the health or change in our environment...in our planet?? Is man comming closer to an end or a new beggining? Both? I can't deny the information that's been brought to my attention in this thread, there's just no way. So I'm open minded to ideas about the mechanics of evolution, and I blame christians for taking much of the Bible too literal and not having enough insight to recognize that life needs to grow and change.

The accepted view is that god has no place in evolution, I'm sure it's in the definition. I believe this is wrong...I think a wise god created life with more than one way to survive.
You may think me crazy, I might be lol. I'll continue reading up on the topic though

 

[Lucky Forward]

Baby Brain Growth Mirrors Changes from Apes to Humans

A study undertaken to help scientists concerned with abnormal brain development in premature babies has serendipitously revealed evolution's imprint on the human brain.

Scientists at Washington University School of Medicine in St. Louis found that the human brain regions that grow the most during infancy and childhood are nearly identical to the brain regions with the most changes when human brains are compared to those of apes and monkeys.

They found that the cerebral cortex, the wrinkled area on the surface of the brain responsible for higher mental functions, grows in an uneven fashion. Every region expands as the brain matures, but one-quarter to one-third of the cortex expands approximately twice as much as other cortical areas during normal development.

"Through comparisons between humans and macaque monkeys, my lab previously showed that many of these high-growth regions are expanded in humans as a result of recent evolutionary changes that made the human brain much larger than that of any other primate," says Van Essen. "The correlation isn't perfect, but it's much too good to put down to chance."

The high-growth regions are areas linked to advanced mental functions such as language, reasoning, and what Van Essen calls "the abilities that make us uniquely human." He speculates that the full physical growth of these regions may be delayed somewhat to allow them to be shaped by early life experiences.

 

[Raist]

Baby Brain Growth Mirrors Changes from Apes to Humans

When will they stop that crap.

Anyways, seen that earlier today. I'm not sure how exactly this is surprising in any way.

 

[Naked Snake]

I've already watched video one and two. These are an amazing find and I'm surprised that I've never seen them posted on GAF.

The ending for video #1 with that cannonball was pretty epic.:lol

Yeah they're great, I wanted to make a thread about them once detailing why I loved them so much, but I'm a lazy bastard. I think my favorite is part 4.

 

[Zozobra]

Yeah they're great, I wanted to make a thread about them once detailing why I loved them so much, I'm a lazy bastard. I think my favorite is part 4.

If anyone isn't at least moderately convinced by the evidence he puts forward for evolution in these videos, then well, they're probably a Creationist.

 

[Mgoblue201]

Here are a couple of interesting science stories:

First from PZ Myers. This story is based on an article that recently appeared in the New York Times. This is kind of a subtle proof of evolution. We're colonized by thousands of species of single-celled organisms, most of which provide valuable services. In some cases the relationship is symbiotic, and we're not even aware of it. From the NY Times article:

“In addition to helping us digest, the microbiome helps us in many other ways. The microbes in our nose, for example, make antibiotics that can kill the dangerous pathogens we sniff. Our bodies wait for signals from microbes in order to fully develop. When scientists rear mice without any germ in their bodies, the mice end up with stunted intestines.”

We easily could have been created with these full features from the start. Instead, we co-evolved with microbes that could already perform certain functions, allowing them to take on the job. But it's even more expansive than that. Microbes can affect how we develop. More from PZ Myers:

Another weird twist is that gut bacteria can affect morphology (or vice versa; physiology influences which gut bacteria thrive). Mice with a genetic predisposition to obesity were found to have a different distribution of gut bacteria; fat mice are full of Firmicutes, while lean mice are loaded with Bacteroidetes. Something in the genetics of the obese mice seems to favor the proliferation of that one species. Cause and effect is not so easily separated, though, since doing a fecal transplant and inoculating the guts of germ free mice with the bacteria from obese mice vs. lean mice has a surprising effect: the mice given obese mouse fecal enemas subsequently increased their body fat by 60%. The bacteria promoted more fat storage in the host animal.

Second, there is an interesting article about whale evolution from Jerry Coyne.

Before I mention their results, I want to show one photo from their paper that supports this evolutionary scenario. Baleen whales, though toothless, develop tooth buds when they’re embryos. In toothed whales these buds go on to become the adult teeth, but in baleen whales they degrade and disappear.

Deméré et al.’s main result is this: they document the existence of a transitional form between baleen whales and their toothed ancestors. This form apparently had both teeth and a small fringe of baleen from the upper jaw. It could thus not only chomp its prey, but strain it. This was a step on the way to the fully-sieving lifestyle of modern baleen whales.

The paper includes two kinds of evidence for a tooth-baleen transition. The first is paleontological, based on a fossil whale, Aetiocetus weltoni, found in Oregon. It dates from 24-28 mya, close to the time when we see the first truly toothless mysticetes. The whale is clearly on the mysticete side of the toothed/toothless branching based on several skeletal features, but has teeth; it’s an early toothed mysticete. But when the authors reexamined they jaw they found previously overlooked grooves (“nutrient foramina”) in the lateral parts of the palate. In modern baleen whales, these slits allow passage of both nerves and blood vessels that feed the baleen-forming parts of the epithelium. (Baleen grows continuously throughout the whale’s life.)

They also found these slits in two other species of fossil mysticetes. It seems likely, then, that these fossils, which occur at just the right time in the fossil record, had both teeth and some rudimentary baleen. They are transitional forms because of both their morphology and the time when we see them.

The second line of evidence is genetic—DNA sequences. The temporary “teeth” in fetal mysticetes have dentin (the calcified tissue that makes up much of the teeth), but lack enamel. Working under the hypothesis that baleen whales evolved from toothed whales that had both dentin and enamel, the authors made the following prediction:

"Given that edentulous [toothless] mysticetes recently descended from ancestors with fully mineralized dentitions, we predicted that enamel-specific SCPP [secretory calcium-binding phosprotein] genes would be present, but not functional, in modern baleen whales."

That is, the baleen whale genome should contain “dead genes” that made tooth enamel in their ancestors. (As I explain in WEIT, when evolution eliminates a structure, it does so not by excising the DNA for the structure from the genome, but by silencing the genes.)

And, by doing DNA sequencing of three enamel-specific genes from 12 species of mysticete, 4 species of odontocete, and some related terrestrial mammals, their prediction was confirmed. Two of these genes were completely dead: they had experienced “frame-shift” mutations that throw the DNA code completely out of whack, as well as mutations to “stop codons” that prematurely terminate the production of a protein. The other gene had a large section missing.

What better evidence for a toothed-whale ancestry for mysticetes? Together with the existence of transitory teeth in embryonic baleen whales, and now the fossil evidence, it’s dead certain that modern baleen whales weren’t created, but evolved from toothed whales about 30 million years ago.

 

[Naked Snake]

^ Wow, forget diet and exercise. The new way to gain or lose weight: get fecal enemas from someone who is fat or thin (respectively)

Science, shit yeah!

x_x

On a serious note, that was a fascinating article, some quotes that stood out for me:

“We have over 10 times more microbes than human cells in our bodies,”

Some surveys suggest that babies delivered by Caesarian section are more likely to get skin infections from methicillin-resistant Staphylococcus aureus. It’s possible that they lack the defensive shield of microbes from their mother’s birth canal.

My youngest nephew (less than a year old) is currently having skin infections and I believe he was delivered by Caesarian section, so the above quote really hit home. I dislike the over sterilization and total germ-phobia that many parents carry out raising their kids these days.

 

[Shanadeus]

Lovely thread!
It's a shame that there are people here on GAF that deny the theory of evolution, and it's great that there's a thread where they can learn more about it.

 

[paranoidfortean]

It's a shame that there are people here on GAF that deny the theory of evolution

I literally do not see how this is possible, but it is. It's one of the major frustrations of modern life to me.

 

[teh_pwn]

^ Wow, forget diet and exercise. The new way to gain or lose weight: get fecal enemas from someone who is fat or thin (respectively)

Science, shit yeah!

Yeah, there have been a lot of these studies in the last 5 years. They can make thin rats obese simply by giving them antibiotics and then giving them bacteria from an obese rat.

I'm not sure I subscribe the the hypothesis that the obese rat's genes determined the bacteria cultures in the gut, because natural selection would have favored the bacteria cultures that make it healthier and more likely to find a mate.

With humans they have sort of reproduced these studies by giving people soluble fiber supplements that favor good bacteria, and these subjects lost fat without any change to their diet while the controlled group remained the same.

And it's not just obesity. Virtually ever autoimmune disease can be induced on a rat by giving them specific bacteria cultures in a clean intestine.

The theory is that bad bacteria cause inflammation, which degrades the intestines, and allows undigested proteins & bacteria waste into the blood, which the body then develops an immune response. What else looks like protein? Us. Our organs. And so it creates an body wide autoimmune slew of disorders.

If the hypothalamus in the brain is inflamed, people never feel full. Put the two together, and it explains why these rats start overeating with these bacteria cultures.

I think some of the obesity epidemic and the increase of autoimmune diseases can be explained by this mechanism. We put antibiotics in so much food, we prescribed antibiotics for everything until 2000, and we increased sugar consumption which favors bad bacteria.


Here are some examples so I don't look like I'm spewing bullshit:
http://www.sciencedaily.com/releases/2010/03/100304142232.htm
http://www.sciencedaily.com/releases/2010/07/100719162643.htm
http://www.ncbi.nlm.nih.gov/pubmed/19386741

I just don't buy the genetics explanation because you can look at photos of people before 1950, and the 1-2 fat people you can even spot are only overweight by today's definition. Our genetics haven't changed.

 

[jdogmoney]

Yeah, hi. In the religion thread, we're having a discussion about morality and stuff. It's all very interesting for the three percent of people that think it's interesting and mind-numbingly boring to everyone else.

Can someone explain to me how morals evolved?

My explanation, while not exactly wrong as far as I know, isn't a very good one, I think.

Humans are social creatures. What is "moral" is, in almost every case, what is good for the group. Murder is bad because people don't want to be murdered themselves. People don't want to be raped. The individuals in the group that do go around raping and murdering and tying everyone's shoelaces together are the ones that are ostracized. Left to wander the wilderness on their own, they have a much smaller chance of survival and close to no chance of finding a mate. Those that play nice stay in the group and get their propagation of the species on.

This gradually led to the development of what we call empathy, which is what I tend to base my moral code on.

I thought this rather clear, but can someone explain it better?

 

[Kinitari]

Sorry to dredge up this old thread!

I was recently entrenched in a conversation in the religious thread about speciation, it was... frustrating, to say the least, so it has kind of inspired me to revisit this thread.

I am planning on fleshing out the speciation section of the OP, going to include vestigial evidence, multiple observable examples of speciation in our life times and probably talk a bit about sickle cell anemia.

Is there anything I am missing? Anything I could add that would solidify the evidence and frame it in a way that even the most doubtful could see that it is a very well substantiated and universally accepted aspect of evolution?

 

[Buttchin]

recent episode of futurama that aired 8/12/10... i rest my case lol

 

[Naked Snake]

Sorry to dredge up this old thread!

I was recently entrenched in a conversation in the religious thread about speciation, it was... frustrating, to say the least, so it has kind of inspired me to revisit this thread.

I am planning on fleshing out the speciation section of the OP, going to include vestigial evidence, multiple observable examples of speciation in our life times and probably talk a bit about sickle cell anemia.

Is there anything I am missing? Anything I could add that would solidify the evidence and frame it in a way that even the most doubtful could see that it is a very well substantiated and universally accepted aspect of evolution?

This might be covered (I haven't read the OP thoroughly), but I think the most conclusive and hard to argue evidence for evolution is in the DNA... Example: Ken Miller on Human Evolution (entire lecture: http://www.youtube.com/watch?v=Ohd5uqzlwsU]

It's great that you're still working on this!

 

[Lesath]

Sorry to dredge up this old thread!

I was recently entrenched in a conversation in the religious thread about speciation, it was... frustrating, to say the least, so it has kind of inspired me to revisit this thread.

I am planning on fleshing out the speciation section of the OP, going to include vestigial evidence, multiple observable examples of speciation in our life times and probably talk a bit about sickle cell anemia.

Is there anything I am missing? Anything I could add that would solidify the evidence and frame it in a way that even the most doubtful could see that it is a very well substantiated and universally accepted aspect of evolution?

Well, since you didn't right out mention it, it would be helpful to include the definition of the word "species." You can also briefly comment on the various ways speciation may occur, mechanistically.

 

[Kinitari]

Updated the OP with some speciation stuff, realized I surpassed the word count . So I will do some clean up later today and try to fit in even more things. What I added to the OP:

You know, I just really don't buy this 'speciation' thing. Where is the proof?

Let me preface this by saying that speciation is an integral part of the ToE - without it, it pretty much falls apart. So to those who say they believe in 'micro' evolution but not 'macro' evolution, understand that you are using creationist made up jargin, these terms had their roots in science, but have been turned into something else. It's all the same.

Let me also state quickly what a species is. It is an animal that can reproduce amongst itself. That's it, once you get to the point where an animal can no longer reproduce with another animal, they are (for all intents and purposes) a different species. There is no higher meaning to the phrase, there is no invisible gene somewhere in all animals DNA that labels them as such, it's simply enough genetic difference.

Now that that's out of the way, picture evidence!

Here we can see the remnants of what were once legs in a whale. The only theory that holds any water for why this occurs is the ToE - more specifically, that whales evolved from land mammals.

Here you see the exact same thing occurring in some snakes!

And on to the more controversial stuff, vestigiality in humans.
Taken from this wiki

Appendix


The vermiform appendix
The vermiform appendix is a vestige of the cecum, an organ that would have been used to digest cellulose by humans' herbivorous ancestors. Analogous organs in other animals similar to humans continue to perform that function, whereas other meat-eating animals may have similarly diminished appendices. In line with the possibility of vestigial organs developing new functions, some research suggests that the appendix may guard against the loss of symbiotic bacteria that aid in digestion.

Coccyx
The coccyx, or tailbone, is the remnant of a lost tail. All mammals have a tail at one point in their development; in humans, it is present for a period of 4 weeks, during stages 14 to 22 of human embryogenesis. This tail is most prominent in human embryos 31–35 days old. The tailbone, located at the end of the spine, has lost its original function in assisting balance and mobility, though it still serves some secondary functions, such as being an attachment point for muscles, which explains why it has not degraded further.
In rare cases congenital defect results in a short tail-like structure being present at birth. Twenty-three cases of human babies born with such a structure have been reported in the medical literature since 1884.

Wisdom teeth
Wisdom teeth are vestigial third molars that human ancestors used to help in grinding down plant tissue. The common postulation is that the skulls of human ancestors had larger jaws with more teeth, which were possibly used to help chew down foliage to compensate for a lack of ability to efficiently digest the cellulose that makes up a plant cell wall. As human diet changed, a smaller jaw was selected by evolution, yet the third molars, or "wisdom teeth", still commonly develop in human mouths.
However, other findings suggest that a given culture's diet is a larger factor than genetics in the development of jaw size (and, consequently, the space available for wisdom teeth):
“Dental crowding in modern humans is considered the combined result of tool use to comminute foods and cooking to modify their mechanical properties, such as toughness.”

Ear
The ears of a Macaque monkey, and most other monkeys, have far more developed muscles than those of humans and therefore have the capability to move their ears to better hear potential threats. Humans and other primates such as the orangutan and chimpanzee however have ear muscles that are minimally developed and non-functional. A muscle attached to the ear that cannot move the ear, for whatever reason, can no longer be said to have any biological function. In humans there is variability in these muscles, such that some people are able to move their ears in various directions, and it has been said that it may be possible for others to gain such movement by repeated trials. In such primates the inability to move the ear is compensated mainly by the ability to turn the head on a horizontal plane, an ability which is not common to most monkeys— a function once provided by one structure is now replaced by another.
The outer structure of the ear also shows some vestigial features, such as the node or point on the helix of the ear known as Darwin's tubercle which is found in around 10% of the population, this feature is labelled (a) in the accompanying figure.

Eye
The plica semilunaris is a small fold of tissue on the inside corner of the eye. It is the vestigial remnant of the nictitating membrane (the "third eyelid") which is present in other animals such as birds, reptiles, and fish. It is rare in mammals, mainly found in monotremes and marsupials. Its associated muscles are also vestigial. The plica semilunaris of Africans and Indigenous Australians are slightly larger than in other peoples. Only one species of primate -- the Calabar Angwantibo -- is known to have a functioning nictitating membrane.

Molecular
There are also vestigial molecular structures in humans, which are no longer in use but may indicate common ancestry with other species. One example of this is L-gulonolactone oxidase, a gene that is functional in most other mammals and produces an enzyme that synthesizes Vitamin C. In humans and other members of the suborder Haplorrhini, a mutation disabled the gene and made it unable to produce the enzyme. However, the remains of the gene are still present in the human genome as a vestigial genetic sequence called a pseudogene.

And here is some (more) fossil evidence!

Camels!

Tetrapods!

Horsies!

Mind you, this is just some of the evidence. This isn't a lightly theorized assumption made by Scientists. This is a thoroughly researched and thoroughly substantiated fact - it happens.




Also, I noticed some people started using my web 2.0 link! Awesome! I appreciate any contribution, and I will go through it soon (probably today after I watch Scott Pilgrim... probably) and update the OP.

 

[Naked Snake]

surpassed the word count

Oh that sucks... would have helped had you reserved the first few posts for expansion I suppose.

 

[Kinitari]

Oh that sucks... would have helped had you reserved the first few posts for expansion I suppose.

Considered it, but I didn't think it would have been this long!

Still, maybe it's better this way, I don't want to make a leviathan of a thread OP too long to read - I can trim some fat and streamline it a bit more.

 

[jaxword]

People need to link back to this thread in the religious threads.

And then, of course, it will be ignored, but at least you can call people out on their blatant hypocrisy.

 

[Mgoblue201]

Tetrapods!

Small detail: Due to the discovery of the tetrapod footprints, the tetrapod evolution might actually have been pushed back to 400 million years ago. But none of the great tetrapod pictures have probably been updated to reflect this kind of weird discovery.

 

[Mario]

The WhyEvolutionIsTrue Youtube channel has posted 10 Episodes (so far) of the Evolve series.

The series looks into how different key biological systems evolved via situational pressures. I have only watched a couple so far but they have decent visuals, and at 45 min an episode they are relatively comprehensive (if still somewhat high level given the subject matter).

1 Eyes
2 Sex
3 Size
4 Flight
5 Skin
6 Communication
7 Guts
8 Venom
9 Speed
10 Jaws

 

[LOCK]

Kinitari your definition of evolution is incomplete in the op. Just fyi

Evolution is a change in the inherited traits of an individual through successive generations. This is done in two different ways: 1)Introduction of new inherited genes or variations, or 2) forces that select for selected traits or variations.

Five main drivers of evolution:
1) Mutations - introduce new traits
2) Natural Selection - selects for and against certain traits
3) Genetic drift - probability that gene transfer occurs generation to generation
4) Gene flow - can prevent and separate groups of species and drives speciation
5) Meiosis - error in genetic reproduction and/or crossing over

 

[Kinitari]

I'll add the videos and the updated definition now!

Screw you mgoblue, I like the picture, possible inaccuracies and all.

 

[DOBERMAN INC]

I have nothing to add that people way smarter than me have not already said way better than I ever could, So I'll just say fantastic OP.

Gonna watch all those links.