Wild cannabis looks much more well, weed-like than the specially bred hydroponic stuff that's all shiny and colorful. When a plant looks unusual like multi-colored corn or square watermelons, there's a good chance people had a hand in making it that way. As far as it's known, cannabis the the only natural source if THC

A lot of plants are very "unique" looking in structure and flower.

Cannabis leaves aren't actually all that unique looking. Many completely unrelated plants have similar shaped leaves. The Japanese maple is a popular one.

And yes, as far as we know, only cannabis naturally produces THC in any measurable quantity.

Other things have Cannabinoids in them, but in low doses. https://www.yahoo.com/video/cannabinoids-without-cannabis-yes-everyday-184410155.html

Weed grown indoors is where you get all the pretty pictures. The plant is grown under near perfect conditions. Temp, nutrients, watering, number of plants in a room, light, etc. So many factors that just one going down could turn your plant into one that's loaded with seeds or just stunts it's growth. Outdoor plants look more "natural" and are usually used for THC extracts. Like oils and topicals.

Very much this. Domestication changes the appearance and features of not just vegetation to suit human wants and needs. Look up any crop, animal or fruit before domestication. Most of them look nothing like what we have today, borderline inedible as well.

Not all.

Not all of them though

That's true, not all. There will always be exceptions.

It's recognizably a chicken, but it's less than half the weight of modern chickens bred for lots of meat. The females are less familiar-looking, as well.

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Cannabis flowers (the part humans smoke) are not pollinated by pollinators

They are wind pollinated, much like corn

So the flowers are not evolved to look appealing to pollinators, like a tulip or whatever, and instead they evolved to disperse and catch windborne pollen. Which is why the marijuana 'buds' are shaped the way they are. It's the female flower that is hairy to catch the pollen from the air.

Corn also has weird flowers for similar reasons (the corn 'strings' play a similar role).

For the leaf shape... idk, no idea, but there are other species with somewhat similar leaves

And idk for sure, but there are theories the THC was acquired from bacteria. That the plant cell absorbed a bacterium similarly to the chloroplast endiosymbiosis theory, and then the bacterial DNA found its way into the plant DNA. Which is fascinating. No idea if this is resolved or not. If you don't know what I'm talking about look up the chloroplast endosymbiosis theory, it's amazing.

Can confirm. I have had weeds in my yard that look like a wild marijuana plant.

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