I think it is you that are inserting the notion of an “animal sense”, and I’m not at all convinced that this exists at all… nor is it responsible for the effect.
I think rather that it comes from the ability to see into the future and plan ones destiny… not very animal like.
Capital is certainly not money in any generic sense… capital are those things which are employed in doing business. In other words, the fixed resources in use by a business to do business. Money can be part of that… certainly… if it exists, but it it does not, then it is what remains… the assets of the business to do business.
Creating capital in any form is inherently valuable… automatically an expression of future use. Therefore to secure your destiny through the power of trade, retaining the value of the means of business (production) in it’s most certain state means defending your personal control over it. In other words, ownership. A fisherman’s net, for example.
But to do all of this means seeing into the future beyond an instinctual sense… and reasoning the utility of a created resource to secure that envisioned future.
Capitalism is the notion that capital is controlled by private owners of it.