Why did life develop reproduction?

I’m not sure that I’m able to ask this question very clearly, but I hope you will get the gist of what I mean.

Basically, why do we feel the need to reproduce?

The desire to reproduce is arguably one of the most fundamental and strongest instincts we have, but why? I know we do, but why exactly do we care if we leave children behind? Why is this such an important thing for us when there don’t seem to be many benefits to ourselves individually?

The only thing I can think of is that as we get older, we may need children to look after us, but is this enough to explain why we each individually care so instinctively about the survival and advancement of the species after we die? Wouldn’t a simpler idea to perform the same tasks (from whatever-started-life’s point of view) have been to work on not getting weaker as we age, or on living forever?

Please note I am not trying to argue for any religious ends (other than it is nicer to think everything doesn’t just end when we die) but do things like this point towards ideas like reincarnation, or consciousness after death?

What are your thoughts?

Apologies if this has been debated before, but it is a rather difficult subject to perform a search on.

P.S. I kept wanting to use the word “evolution” throughout this post, but I suppose evolution couldn’t really have had anything to do with coming up with the reproduction idea seeing as it relies on it from the start! :slight_smile:

If an individual wants to live, whats in it for him? nothing as far as i can tell. The desire to survive is hard wired into our brain from an outside source. I don’t think it is an individual oriented thing, i think it is an outside imposed survival mechanism. I don’t think an individual’s desire to look out for his own survival is different than keeping the species alive as both end up furthering the cause of living. The end result is the same from a macro perspective, life goes on. It wouldn’t without one or the other.

On the opposite side of the fence regarding the idea of a selfish gene, the fear of death can be nearly conquered if people are willing to die to benefit a larger entity (their church, their country, their political cause, etc). So its a mixture of individual desires to survive and the desire of ‘the unit’ (whatever that is) to survive.

Are we talking about the ability to reproduce or the urge.

If the latter, then the answer is fairly simple; the more desire an organism has to reproduce, the more offspring it is likely to have; if these offspring inherit a similar level of desire to reproduce, then they too will produce more offspring; an organism that lacks the desire to reproduce will remove itself from the gene pool by not bothering to reproduce.

Good point on the survival. I was mainly wondering if there could be some higher purpose we don’t understand that causes us to reproduce, but this could apply equally to the survival thing. The thing I’m interested in is what could be the outside source you mention? A God, an alien experiment? Do these things seem to point towards something out there, or could it all be coincidence or chance?

Oh yeah, I understand that. I’m more interested in what specified that being eliminated from the gene pool was a bad thing? I realise we can’t really come to any conclusions, but it does seem to point to some greater cause, and I was wondering about people’s views on that. :slight_smile:

Could it be…

  1. There is a God or some higher being?
  2. An alien experiment.
  3. Total chance causes all of this, it’s just how things panned out as life developed.

I don’t think you do understand - it isn’t a case of whether being excluded from the gene pool is ‘good’ or ‘bad’ (whatever that means), it is that lack of the desire to reproduce results in lack of reproduction, lack of reproduction means that the organism (or its genome) disappears without a trace. Everything that has the deisre to reproduce, reproduced(or tried to), everything that didn’t have the desire, died out; what is left at the end is that everything that is still here has the desire to reproduce.

Your position (which perhaps I am misunderstanding) seems to be a bit like being astonished that the winner of a race is always the guy who can run the fastest.

That’s right…
the ancient seas were no doubt full of tiny colonial organisms, made up of smaller organised units which clumped together to feed at each others tables. This phase of life could have continued for a long time before accurately self replicating molecules like RNA and DNA allowed the reproduction of a copy of the organism that used them correctly.
The primordial seas would soon consist of copies of those first self replicating organisms, which would have eaten the other non reproductive ‘soupiformes’ to manufacture copies of themselves.
If any non selfreplicating protien cells formed at any stage in history after this event, they would soon be devoured, whih is why they are not found in nature today.
This invention, or discovery, of information technology by such primitive lifeforms is the most incredible stage in all evolution, yet here we are.
By the anthropic principle, it must be possible for it to have happened at least once.

Mangetout - Ah yeah, sorry, I was misunderstanding! I see what you mean now, and you’re right. :o

Also, thanks eburacum45 for elaborating. :slight_smile:

I wasn’t considering that there had been non-reproducing/non-survival-concerned organisms that had simply died out, I was too stuck on the idea that it was something that all (I assume) forms of life do today! That makes more sense to me now, and I suppose it would be getting too much into “Why did life start?” and “What’s the meaning of life?” territory to take this much further! :wink:

Thanks guys!

To the intelligent thoughts that have already been expressed in this thread, I would add that if you are the least bit interested in this topic, you should run out and get a copy of The Selfish Gene by Richard Dawkins. It’s a fabulous book.

Many thanks, Lucwarm, I am interested and will check out the book.

Sorry to waste your time guys, but hey, I’m learning about something new to me! :slight_smile:

The Lucifer Principle is a good read too.

As soon as I read the OP, I decided to recommend that very same book. Good read, and it directly addresses the question laid out here.

I agree with you, Mangetout, but just wanted to add that there are people alive who have zero desire or urge to reproduce, which you seem to indicate wouldn’t happen. For some reason, those darned ‘no-bio-clock’ people keep popping up :wink: Granted those people are a minority, but they do exist.

In discussions like these we have to distinguish between ultimate causes of behavior, which usually apply to a species as a whole, and proximate causes of behavior, which apply to individuals.

It’s obvious that the ultimate reason for sexual desire is to perpetuate the species. But that doesn’t mean that all individuals want to reproduce. A man may want to have sex simply because it feels so good, and may actually go out of his way (by wearing a condom, say) to PREVENT reproduction.


Suranyi, I understand what you’re saying, but I was commenting on something different. It seemed to me that Mangetout was implying that life reproduces because anything that didn’t want/wasn’t able to reproduce died out, leaving only those that had the desire and ability to reproduce behind.

I was only pointing out that it wasn’t quite so simple as that, since there are people who are unable to reproduce, or dislike the idea of reproducing around today. Therefore, much more complex stuff was going on than just a binary ‘have ability and desire to reproduce vs. don’t have the ability or desire to reproduce’.

But I agree in conversations like this, it is helpful to differentiate between the individual and the species as well as the desire for sex and the desire to reproduce. I just made my point, because so many people seem to think everyone ultimately has a desire to reproduce.

Replication defines life. The consequences of reproducing is the only quality that delimits the semantical definition. Hence…

Well, one thing is that the biological imperative to reproduce is expressed in all sorts of subtle and complex ways (as for example the sterile workers in social insect colonies, who don’t reproduce but instead labor on behalf of their queens, who are actually their genetic near twins). So, an individual who doesn’t reproduce may still look after their genetic interests by helping to take care of the offspring of their siblings or other close relatives. (I believe I’ve seen that proposed as one possible explanation for how a “gay gene” might have been selected for.)

Even more relevant in this case is that humans are much more complex than bacteria, or even bees. We have evolved minds, and cultures, which allow us to sublimate, subvert, or transcend our biological programming in all sorts of ways.

I did not double-post to this thread.

Nothing to see here.

Move along.