why is smoking so addictive what's the evolutionary purpose

I've often wondered what evolutionary advantage tobacco has in being addictive.

It could jut be a coincidence, with so many plant species existing there's bound to be one or more that have addictive qualities.

>>8815127
There is no direct evolutionary purpose to addiction (from the perspective of the addict). Addiction is a side effect of molecules that work on the brain's endogenous reward system.

Certain behaviors are reinforced through neurotransmitter (e.g. dopamine and serotonin) action. If you eat when you're hungry, that act is rewarding, and so you repeat the behavior. This is is obviously adaptive in the evolutionary sense.

Nicotine and related substances act directly on the brain's reward system, and more strongly than 'natural' behaviors, so these substances are likely to reinforce the behavior that led to the substance being ingested. And with each time the behavior is repeated, the reinforcement becomes stronger, in time leading to structural changes in the brain's reward system.

>>8815127
Before widepsread agriculture, the only way to get tobacco was to kill a wooly mammoth and suck the tobacco out of its stomach (wooly mammoths also loved tobacco, and that's part of the reason why they went extinct, but their stomachs couldn't digest it). This forced tobacco addicts to be strong and courageous, which is why their genes were more likely to get passed on.

>>8815188
But this doesn't explain why tobacco is so much more addictive than, say, weed

>>8815206
???

depressing post

>>8815127

because smoking tobacco is wonderful.

it's the perfect form of the perfect pleasure, exquisite but never satisfies.

>>8815259
The two have a completely different pharmacokinetic profile. Weed acts on the endocannabinoid system, not directly on the reward system in the ventral striatum.

Substances that are more addictive usually act on dopamine receptors (or prevent dopamine reuptake), and have a strong affinity for those receptors. Nicotine is special in that it acts on acetylcholine receptors, but this indirectly also triggers dopamine release. Weed also leads to dopamine release, but to a much smaller extent, hence it's less addicting.

evolutionary purpose is my favorite /sci/ meme

>>8815273
ventral tegmental area senpai

>>8815284
>ventral tegmental area senpai
Both VTA and striatum are involved in reinforcement, but thanks for the addition

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43KB, 576x512px

>>8815127
>what's the evolutionary purpose or is it just an accidental side effect of the 'optimization algorithm'
You notice that usually the dumbest and laziest are drug addicts.
Weed *weeds* them out.