One of the key problems in discussing biology is the need to avoid framing everything within the context of human experience. It is important to remember that a significant number of life forms are plants and single-celled organisms. In addition, we have to consider what we actually mean by the word "life" before we can create a useful picture of events.
To begin this exploration we need to consider what we mean by "life" and examine it from its most basic components. We think we know the difference between living and non-living, but it's harder to describe it than one might originally think. For our purposes we can use one particular characteristic to differentiate between the two states. Non-living things or inanimate objects are subject to the forces around them and are changed by them, such as erosion or material degradation. Living things are characterized by being able to acquire and use external energy to maintain an internal environment which sustains them.
However what is being sustained in this description? The simple answer is ultimately chemical reactions. These are molecules that form a variety of structures which are repeatable and can be used to extract the energy from external sources for internal exploitation. Once this mechanism has been achieved, there is a need to perpetuate the process (since no reactions can run infinitely) through reproduction.
While this description may sound quite cold or even "sterile", it is important to remember that every living thing is subject to its internal chemistry whether it be the ability to process food, reproduce, or generate the emotions it feels. These are ultimately chemical reactions.
If the chemistry is disrupted the organism will die. It is the chemistry that gives rise to the structures that define the living thing, it is the chemistry that will allow it to survive, and it is the chemistry that will determine how it reproduces and result in a new copy of itself.
Once we understand that the underlying chemistry is the driving force for all life, then all other manifestations must be interpreted from that perspective. However, instead of exploring every nook and cranny of life's diversity another simple principle can be taken from this to explain large scale behaviors, such as those present in sociobiology.
This principle is that because of how life operates, we cannot propose any process that requires intentional actions or consciousness in order to work. While there may be varying degrees by which such actions can occur in living things, they cannot be the driving force because ultimately the "decision-maker" is simply chemistry.
While Richard Dawkins proposed a "selfish gene" to explain this viewpoint, the position was actually overstated by using the word "selfish". Genes and chemistry behave in a "self-interested" way because there is no other way to describe their interactions, but selfishness implies a more directed activity which simply doesn't occur. Once we remove some of the connotations of "selfish" we can readily see that many self-interested behaviors would give rise to cooperation and it is this trait which will ultimately determine how living things survive and succeed.
Once again we're trapped by our use of language with words like "selfish" or "cooperation" denoting intentional actions, but it is important to recognize that these are only approximate descriptions that can be observed and don't imply a conscious intent by the organisms themselves.
In an experiment conducted by Robert Axelrod, computer programs were allowed to "compete" with each other for points, and the highest point accumulation would indicate a successful strategy. Interestingly enough, the highest points were garnered by a unique element of game theory called TIT FOR TAT, where cooperation is gained by ensuring that the behaviors between two entities are mirrored, so that each recognizes that cooperation will pay off better than competition.
What makes this experiment significant is that it demonstrates a mathematical approach that can be analyzed and demonstrates how artificial entities (computer programs) can reach a cooperative decision without themselves being able to think. This approach neatly fits the requirements of how cooperation can arise between molecules or chemical processes. From this we can consider that such an algorithmic mechanism can explain how such cooperative processes, such as multi-cellular organisms and even sexual reproduction, can occur.
In addition, the mechanisms of evolving structural changes in a living system are much longer processes and may not be timely enough to provide solutions for living things striving to survive. Once again, we find that a useful short-cut through evolution is in cooperation. We see this occur in predators as well as prey animals when the formation of groups allows for greater hunting success or predatory protection simply by the act of cooperating rather than physical changes to the animal itself.
Consider that cooperative predators gain by being able to bring down larger prey animals than they could in isolation. This reduces the risk of injury to individuals and provides a more stable, consistent approach to acquiring the outside energy required to sustain the individual members.
Similarly when prey animals group together, it reduces the likelihood that any particular animal will fall victim to a predator and tend to result in the weakest members being the most likely to be killed. This creates a positive evolutionary force on the group which directs its future evolution.
Once a level of cooperation is attained, then the evolutionary selection pressures on the species also change to promote cooperation versus "going it alone". Those that are part of the group tend to do better than those that are alone, so over time we find that the cooperative animals survive while others fail.
Consider the scenario using human beings. An individual human has zero survival potential. Many people resist this idea because they think that if one simply possesses survival skills they can do quite well for themselves. However this misses the point from a biological perspective. Species success is not based on the survival of adults, but rather on their ability to produce offspring which themselves can successfully survive. When one considers the additional requirement to find suitable mates, it is easy to see that an individual with survival skills is irrelevant. The much larger framework must exist for success.
In conclusion we've drawn a very sketchy picture of how, coming from chemical origins, we could arrive at a cooperative group of individuals. It should also be clear that many details are missing because of taking such a broad view of events. However, it should also provide some insight into the significance of sociobiology. Not as an incidental curiosity regarding group behavior, but as a significant evolutionary force that provides an alternative to species survival that genetic structural changes by themselves are insufficient to do.