Either altruism is possible, or it isn’t, and this goes for both nature and humanity.
I happen to think altruism is possible, and that the human being is just one of the most striking examples of it. Equally striking are our bodies themselves, composed of trillions of cells who somehow have chosen to participate in generating and developing this larger thing we call ourselves.
But I suppose at the end of the day it all depends what we want to distinguish as a “self.” Point me in the direction of an organism that isn’t dependent upon lower manifestations of self (cells, molecules, atoms, photons). Attributing selfishness to something in nature is a function of a grammatical choice (which depends on the type of attitude we want to take towards “nature” or “reality”). It is not a representation of reality, but something projected by the structure of our language (ie, our consciousness) onto that which grabs its attention. What grabs its attention is not necessarily anything to do with the features of an independent reality. It has to do with the grammatical habits we have picked up as a result of our attempts to communicate with “nature” (everything other than “ourselves”) using language. Language is not a picture of the world, consciousness is not a mirror. What we call “ourselves” is involved in giving rise to the “world” we conceive of as existing independently of us. We are not passively observing and reflecting, but actively shaping and partaking in the ongoing unfoldment of reality. When you describe “nature” (the other) in a particular way (as selfish or altruistic), you are projecting your understanding of a language shared with other speakers (and the self-esteem thereby imparted). You are not explaining mind-independent facts about reality itself. In short, you see what you are. Nothing more, nothing less. In a similar vein, everything you know is something that you do. Knowing and doing are not two.
Evolution is what we call the process which emerges from the ongoing dance between the masculine and the feminine. In material terms, this means between matter and time. In biological terms, between genes and bodies, or sperm and egg, or fetus and womb. When you only see the masculine, the feminine loses significance. This is akin to admitting only the selfishness of nature, while dismissing entirely the selflessness. There is no point in over emphasizing the point despite the space surrounding it, because a point only arises in relation to the space around it! The genome helps to guide the organization of the organism-environment, whose behavior feeds back into the structures guided by genes in the form of development and learning (neurogenesis and synaptogenesis). The phenomenon of genome-organism-environment is a closed loop, and there is no gap separating the gene from nature. There is nothing to hoard because there is no one apart from the loop to be selfish.
When you see both the figure and the ground, the tree of knowledge remains firmly rooted in reality. The tree of knowledge is the nervous system, most ancient and wise in its human incarnation. It has two hemispheres, one for the writing and one for the wall. Do you see it? You need both to be alive. If you are lucky enough to discover the fruit shared by each, you may become eternal as well.