As physics currently describes life, we should not be talking about species. The idea would be an abstraction, a way to classify individual animals having similar anatomic, physiological, and behavioural features, who produce offspring when they mate. That said, we can go further to claim that there is no individual living being, which means that we ourselves do not exist. If everything were nothing but a collection of molecules exhibiting only those properties associated with that level of matter, animals and species would be figments of our imagination, images and ideas imposed on something very different. But, what then is imagination and thought, and who is imagining and thinking? What usually happens when the hypothesis is found to counter the evidence, is that we throw it out. In the case of Evolutionary Theory however, we throw out the evidence.
Intellectual alienation from reality aside, we can connect with other living creatures, seeing them for what they are, each in itself and also as an expression of something greater. One may wish to contemplate the interaction while petting the next cat you meet. That cat exists as an individual being in itself, defined by its catness which incorporates the particular form that visually identifies it as such and enables it to do cat things in space and time. Within that relationship one will realize that species are no more solely in our minds than is the cat itself.
Material forms of being exist as themselves, atoms comprised of more basic forms, first created from what was an amorphous universe of pure light before photons, itself having been brought previously into existence. Within space and time, they follow their nature, God permitting, exhibiting the constants that govern their relationships and include the laws of physics, such as that of thermodynamics. As they exist, individual single cell organisms exist, as themselves and exhibiting the qualities that make them what they are. These include their molecular make-up, which is incorporated into the wholeness, the being that is each one. We who are made of organ systems, comprised of cells engaged in countless varied physiological pricesses, are likewise one in ourselves, and by virtue of our human nature, one with everything we connect with by means of our relational nature (aka, ultimately our capacity to love).
There is no apparent randomness in any of this, only to those adhering to the shared illusion propagated through the narrow and distorted vision of creation that the social phenomenon of modern science provides.