The Dual Evolution?

Question

Let me first say that I a Christian and believe in creation. However, I pose a serious question.

If evolution is true, then at one point a pair of animals with "exact" DNA had to be in the same place at the same time and be able to procreate. Right? I say exact because humans share 98% or some similar percentage with primates and together we cannot procreate.

Therefore, this is what bothers me about evolution and I would like it explained to me. At one point, organisms changed from cell division to sexual reproduction. Two of these organisms had to be in the same place on earth, as well as at an age of reproduction, and able to procreate.
Have I missed the point of evolution? I am asking for open and educated debate. We could quote Genesis, but lets not. Use logic to discuss this, otherwise it might go down hill fast.
Please respond.

Answer 1

OK, there are two misconceptions here. The first has been addressed somewhat, regarding the origin of sexual reproduction. It's not like one bacterium decided to do this and then had to convince another one. The second is that anyone needs to mate with an identical twin.

Bacteria today gain considerable advantages by sharing genetic material, instead of staying with the mother to daughter pattern of asexual reproduction. At least some types of antibiotic resistence are passed this way, resulting in much faster spread of antibiotic resistance than if it were just a matter of cells that mutated a resistant gene surviving the antibiotic and making daughter cells by cell division. Instead the survivors of antibiotic treatment "have sex" with other bacteria and spread this successful gene that way as well, not because the bacteria know to do this, but because they have genes that cause them to share all sorts of genetic material, because those genes that cause this indiscriminate sharing are advantageous.

One can envision that starting with just one cell developing genes to copy genes into other bacteria. Then after that it could become a mutual thing when this copying trait spread. There are of course many possibilities for how it actually happened the first time. But they don't require identical organisms. In fact there would be no advantage to this between identical organisms.

That brings me to the second point. It is false that procreation takes place between organisms with identical DNA. Human identical twins might try to procreate sexually, but they're not going to get very far. But even if you forget about sex chromosomes, no pair of humans except for identical twins has exactly the same genes. So that's not a requirement for the development of sexual reproduction.

What is required? The fossil record shows species splitting into two and going their separate ways. Presumably when such a split starts, the organisms of what will become separate species could still procreate, but don't, because the different subspecies are living in different places or because they've developed different preferences for mates or whatever else. At no point is there a single individual at a loss for a mate. There's always another individual who's close enough.

At the other end of the evolution of sexual reproduction, there didn't have to be specialized genders at the beginning. There could be one bacterium or larger cell sticking it to another without the second being specialized to receive genetic material. Eventually sex worked well enough that mutations that made the process more sure by causing the development of genders were favored. Again at no time is there an individual who is so finicky for a mate that this can't proceed by evolution.

Answer 2

Sexual reproduction need not have started in the way you describe. It may well have started as a sort of hermaphroditism, where organisms, while seeming the same, somehow started to share their DNA, or, as in the case of bacteria, some DNA is encapsulated in the plasmid, and shared with other bacteria. From here, is it such a leap to believe that one mutated bacteria was formed that had only the one type of DNA, say, the plasmid, for example, and shared that around with more bacteria than dividing alone would produce. Or a hermaphrodite was born missing part of its DNA, but the part which remained could pass itself on to more partners than other organisms.
This is a simplified version, but these scenarios quickly come to mind, and do not need the coincidence of two mutations occurring at the same time, a male and a female, in the same place.
Other, more expert respondents may explain it better, but you need to be able to accept the answers as given.

There are too many problems with Creation for me to accept it without evidence. I do not feel affronted by realising that I am related to Apes, monkeys and pond slime.

Answer 3

> I a Christian and believe in creation
Do you believe everything Moses tells you? Moses is the only source for Biblical Creation. Go back and read your Genesis and Exodus.

> If evolution is true, then at one point a pair of animals with "exact" DNA had to be in the same place at the same time and be able to procreate. Right?
Happens all the time. You went to college to meet the girl you married, right?

> Two of these organisms had to be in the same place on earth, as well as at an age of reproduction, and able to procreate.
So you went to college. Plenty of women of the right age there.

> Have I missed the point of evolution?
Yes. The point of evolution is that allele frequencies, over time, can change in a population. Over a long long period of time, the accumulated changes can cause one population to diverge from another, essentially becoming a new species.

A mini-dachshund is descended from wolves, but is not itself a wolf. This process can occur in nature as well.

Answer 4

I will add to Gary H's "third theory".

Imagine, if you can, the female egg cell being the equivalent of a bacterium. Then, imagine a sperm as equivalent to another smaller faster bacterium. In effect, the egg "eats" the sperm and absorbs it's genetic material.

Bacteria is famous for absorbing genetic material from other bacteria and this seems to me like how sexual reproduction probably evolved. Naturally, over a billion (with a b) years or two.

It is often hard to understand how evolution could have happened because of the huge amount of time involved. We humans have such a short life span that we cannot easily envision 10,000 years (which is about how long it has been since agriculture was invented) going by. And, you have to multiply those 10,000 years by 100,000 to get to even one billion.

Answer 5

First of all, only some species even use sexual reproduction, but I imagine it arose from something like this:

Something like what we consider sexual reproduction evolved before some species even went multicellular. Some of the protists are still seen to do "conjugation", where some cells will exchange genetic material with each other, even though they don't have what you'd call sexes. These cells have 100 % of the same genes, like you do with another human being, but the content of those genes (alleles) can be different - like why you look different than another human.

Conjugation provides the evolutionary advantage of creating more variety in daughter cells. As animals etc. became multicellular, they kept up the process, only they let a few cells of the body specialize to combine easily with cells of another organism of the same type. I would speculate that something very much like like this process bridges the gap between asexual and sexual reproduction.

Answer 6

Your mistaken assumption is that life started out as simple sexually reproducing organisms that had DNA.

The origin of life on Earth starts with a process of abiogenesis. Many of the steps that would have been involved can be replicated under laboratory conditions. Many scientists believe that natural chemical reactions led to an RNA phenotypic world which chemically evolved processes such as protein construction. But this view is debated by other scientists who believe that chemical reactions could have produced sustained methods of protein construction and storage of information independent of RNA, and then later bonded with phenotypic RNA. These scientists point to lab experiments which suggest this is a far simpler process of starting life.

But however life did start, the time it took to go from simple shards of RNA until there were sexually reproducing organisms with DNA was approximately 3 billion years. During that time species were slowly evolving by means of asexual reproduction. Some of the major events in evolution during this time involved different species asymbiotically combining their genetic material (we still see evidence of this, as in mitochondria in human cells, etc.)

Answer 7

I believe in creation too, and consider the Big Bang as evidence of it. Creation of an entire universe from literally nothing implies a creator, doesn't it? Anyway...

Wikipedia mentions 4 theories to the origin of sexual reproduction, some of which are described by posters above - can I just cutnpaste?

"Origin of sexual reproduction
The most primitive organisms known to reproduce sexually are protists (primitive unicellular eukaryotes) such as those that cause malaria.

Organisms need to replicate their genetic material in an efficient and reliable manner. The necessity to repair genetic damage is one of the leading theories explaining the origin of sexual reproduction. Diploid individuals can repair a mutated section of its DNA via genetic recombination, since there are two copies of the gene in the cell and one copy is presumed to be undamaged. A mutation in an haploid individual, on the other hand, is more likely to become resident, as the DNA repair machinery has no way of knowing what the original undamaged sequence was.[18] The most primitive form of sex may have been one organism with damaged DNA replicating an undamaged strand from a similar organism in order to repair itself.[19]

Another theory is that sexual reproduction originated from selfish parasitic genetic elements that exchange genetic material (that is: copies of their own genome) for their transmission and propagation. In some organisms, sexual reproduction has been shown to enhance the spread of parasitic genetic elements (e.g.: yeast, filamentous fungi).[20] Bacterial conjugation, a form of genetic exchange that some sources describe as sex, is not a form of reproduction. However, it does support the selfish genetic element theory, as it is propagated through such a "selfish gene", the F-plasmid.[19]

A third theory is that sex evolved as a form of cannibalism. One primitive organism ate another one, but rather than completely digesting it, some of the 'eaten' organism's DNA was incorporated into the 'eater' organism.[19]

A comprehensive 'origin of sex as vaccination' theory proposes that eukaryan sex-as-syngamy (fusion sex) arose from prokaryan unilateral sex-as-infection when infected hosts began swapping nuclearized genomes containing coevolved, vertically transmitted symbionts that provided protection against horizontal superinfection by more virulent symbionts. Sex-as-meiosis (fission sex) then evolved as a host strategy to uncouple (and thereby emasculate) the acquired symbiont genomes."

Answer 8

These "organisms" were single-celled, so I think one fault in your logic is that you're assuming they were multi-celled creatures that we have today. Early Earth didn't have a bunch of exotic, different types of organisms running around, so that they had to be lucky to find another of their type. Rather, the evolution of life using DNA as a template created simple organisms that were likely to be similar. (Actually, RNA was probably the first genetic material.)

In this scenario, it was easy to find a similar individual, since - being single-celled - there were tons of them. Further, they started off in the ocean, so it wasn't a problem getting around.

The first sexual reproduction probably resembled something close to bacterial conjugation, in which little strands of the bacteria reached out to other bacteria and transferred genetic information. From there, the steps to sex as you're thinking about it were just as logical and inevitable as the evolution of multicellular, differentiated organisms (those with distinguishable tissue types like eyes and livers).

The point you missed about evolution is that it takes an enormous amount of time to change the populations. Early organisms didn't evolve in leaps and bounds, as from single celled to full blown sex. Think on smaller organismal levels, and over longer time periods, and evolution might make more sense to you.

Answer 9

There are plenty of steps between simple cell division and sexual reproduction. Hydras are simple multi-celled organisms that reproduce by budding. Many other simple multi-celled animals produce gametes that they then can self-fertilize or exchange with other individuals. It's not difficult to see how sexual reproduction could have evolved from this, particularly since sexual reproduction gives a huge advantage to a species by maintaining variation.

Answer 10

If evolution is true?

What do you mean if? Have you read any works on Evolution? Have you followed any scientific experimentation that has been replicated time and again that disproves thousands of years of experimentation and thousands of experiments all done independently of one another?

If so, where were your results published?