Just as the rings of a tree means that the tree is x number of years old, dark clouds and rumbling of the sky means that it will storm or rain. I think "meaning" is off-putting to those who are afraid that meaning means a Platonic universal, or that it means some value that only humans can understand or possess (as in, there is a "meaning" to life). Naturalists who are reductive naturalists in their approach tend to think of meaning in precisely that way and thus reject it, thinking meaning is somehow "outside" of nature or simply a "construction" in the mind of human beings. A radically reductive naturalist would keep emphasizing how without human beings there couldn't be meaning in the world. In this sense they would say, perhaps in the vein of some form of nihilistic naturalism, "life is devoid of meaning," or if humans are honest there just simply isn't meaning "out there" in the world. Yet isn't it anthropocentric pride to think that human beings have some special "status" so as to be the only forms of existence to bring meaning into the world?
There are obvious problems with such a view of "meaning." In actuality, meaning is nothing more than the natural action of an indexical sign. It is simply "information transfer." All of nature is constantly sign-ing, whether there are human beings there to interpret the meaning of those signs or not. The natural world is constantly in a state of information transfer through the interaction of agents or bodies. Because there is nothing non-natural, and because there are bodies present throughout the world (even molecules interact semiotically, this is the basis of chemistry and thus how various bonds form - as in, various compositions where behaviors of atoms mean such and such an atom is of a specific type and is able to bond with such and such other atom), we cannot say that human beings and the symbolic cultural realm of meaning is somehow "separate" or different from the ubiquitous natural semiotic that includes all of the material realm or perhaps even its structuring conditions.
Biosemioticians do not think there must be intelligent interpreters there in order for meaning to happen. All of nature has mentality present within it insofar as nature communicates with itself. So long as events occur in the universe there will be data transfer. Even within the cold void reaches of space, so long as the universe is expanding the change present within the universe indicates various happenings and events, thus data that has occurred for expression. I suppose the only time the natural semiotic would die is if the universe in its growth died (but is it possible for all universes to simultaneously die in some absolute manner such that there was absolute nothingness, and yet, even in such an absolute form, that "nothingness" would still reify itself to be and mean what it is, as itself as some state that has occurred!)
However, back to the natural semiotic that is present now. Regardless of whether or not there are human beings on the planet the number of rings on a tree stump still indicates that the tree is x number of years old. In this way the expressed information is objective, as the "meaning making" or action of data expression is found within the semiotic communicative power of the agent in question, which is the tree stump. This is what Peirce called the semiotic object. The "sense" of the sign - its data or information - is represented in the form the sign takes and is available for other interpretants to discover. Red dust on Mars would still mean rust even if no one ever saw the planet. And rust means that Mars cannot sustain a certain form of atmosphere. I couldn't help but thinking of this as Matt walked through the forest: look at the color of trees around him, where the healthy color of the pines indicated the health of the tree via pine needles, and so on.
In the triadic exchange of data, certain possibilities are afforded and others are denied. Objects communicate actions to other objects which in turn stand in for signs. Signs are objects and objects signs. What's "in between" is both sign and object in a different sense. And so on. Or again, citing Peirce, "Namely, a sign is something, A, which brings something, B, its interpretant sign determined or created by it, into the same sort of correspondence with something, C, its object, as that in which itself stands to C."
True, Peirce states that 'A sign... [in the form of a representamen] is something which stands to some body for something in some respect or capacity." But as Matt pointed out, so far as there are "bodies" interacting there will be information transfer in a triadic relation (just like in chemistry). It is also how information may be regarded as "mind" or mentality when the sense of that information is distributed before other acting bodies.
Belfiore's book The Triadic Mind emphasizes such a point (see HERE). Matt's video is below, about six minutes in length and worth a watch.