I am not sure if this question is best suited for this stack exchange, but I couldn't think of a better one. Why do animals with brains desire things? What is the evolutionary function of desire? What is its biological purpose? I have been wondering this for some time.

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    Desire is the trigger to search for necessary ressources. Without finding necessary resources there is no survival.
    – Jo Wehler
    Nov 8, 2023 at 10:57
  • Note that nowhere near every trait has “an evolutionary function.” Traits often arise as side effects of evolutionary pressures. Thus it would be misguided to suppose that aging serves an evolutionary function. Instead, it is but the result of optimally allocating resources to traits that are evolutionarily driven—such as reproductive success—rather than invest in maintaining youthful vigor. Since organisms are likely to fall victim to such external hazards as predation, disease, or illness at some point, enhancing the sustaining of youthfulness ends up a poor investment. Nov 8, 2023 at 14:35
  • Probably raising dopamine levels in the brain, facilitating beneficial activity.
    – Philip Klöcking
    Nov 8, 2023 at 14:44
  • Sex, essentially.
    – Olivier5
    Nov 8, 2023 at 15:54
  • This is a personal assessment: a byproduct of all interactions is attraction/rejection (e.g. you buy a tasty apple at a good price, then you get attracted to the seller to repeat the interaction; molecules interacting in a gas tend to dispersion, that is, rejection, etc.). Desire is an expression of attraction, with the goal of sex/reproduction/survival. Getting attracted to someone finally increases the probabilities of species persistency.
    – RodolfoAP
    Nov 8, 2023 at 16:24

3 Answers 3


Life has evolved to behave in a way that increases the chance of passing on genes. Generally, you are more likely to pass on your genes if you eat, mate, avoid predators and other risks, etc. Your body and brain have evolved to encourage you to do those things through chemical reward systems. When you eat, for example, that triggers the release of chemicals that give you a pleasant sensation, so that you are motivated to repeat the experience and avoid malnutrition. Presumably, similar processes encouraged our ancestors to find warm, safe caves to live in, to have ornaments that attracted mates and so on. Desire, therefore, is a mechanism that encourages the search for outcomes that are likely to increase your chance of survival and procreation. Today, some of those selection pressures that influenced our evolution do not apply to the same extent, but the associated mechanisms still remain.


The desire for food and procreation allow the animal to survive and replicate its genes. A lack of desire would be an evolutionary disadvantage. Excess of desire would cause risk taking and lower chance of survival. We humans have animal desires that may not be in our best interests as individuals, practically or ethically.


If you start with the premise that knowledge is not innate but desire is

Then that desire creates a curiosity to explore your environment from whence you are concieved and continue from birth.

This desire causes you the want to interact in our environment and learn that once you begin learning, you can acquire knowledge about your environment and alter your behaviour as a consequence of that knowledge and develop your conscious self.

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    Nov 8, 2023 at 16:40
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    @Community Why do I have support my answes with citation and reference when other members of the community do not. No offence but that sounds discriminatory to me. My answers are not inflammatory and do not contain content that can be deemed offensive can you explain why other members of the community are treated differently than I am. I'm not trying to be clever or smarter than anybody else and I have responded with humour to other members of the community posts. I understand that the references are important from a reputable source,I have no credentials Iam just an ordinary man.
    – 8Mad0Manc8
    Nov 8, 2023 at 17:23
  • @Community And if you must know that I know about dopamine as I have to take reuptake inhibitor to control my illness and the dopamine is a reward for particular action.. But that really doesn't explain how desire actually exists in the world because it didn't vote from inanimate matter unless you can come up with another explanation!
    – 8Mad0Manc8
    Nov 8, 2023 at 17:41
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    Sorry @8Mad0Manc8 the bot did this to you, was my fault (this time). You are right, it doesn’t make sense to send out such messages to new users if higher level moderators do nothing about older users violating the same standards. When I’m behind the wheel of the bot, I won’t flag anyone else for this reason again (especially since this bot only targets new users). Very sorry about this.
    – Hokon
    Nov 8, 2023 at 22:45
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    @Hokon Thanks for the apology :-)
    – 8Mad0Manc8
    Nov 8, 2023 at 23:04

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