Biology perspective on collective intelligence
From Handbook of Collective Intelligence
As Malone and Crowston (1994)  observe, "many parts of biology involve studying how different parts of living entities interact. For instance, human physiology can be viewed as a study of how the activities of different parts of a human body are coordinated to keep a person alive and healthy. Other parts of biology involve studying how different living things interact with each other."
Clark and Mangel (1986)  examine how group foraging behavior in animals evolve. Specifically, they consider the impact of feeding rate, survival probability, within-group competitiveness, and information use on individual and group fitness for survival. They develop the concept of Behaviorally Robust Strategies in animal groups.
Mallon et al. (2001)  consider mathematical models of how ants and bees collectively decide which new place shall be where they nest. While bees are able to indicate the quality of a candidate site with the vigor of their dances, ants indicate quality by starting earlier in recruiting other ants to the site (rather than keep looking for new sites).
Bee scouts who have done their dances stand aside to observe dances by bees for other candidate sites; they do not continue dancing to do more promotion, nor do they interfere with competing dancing bees. This is a form of unprejudiced opinion polling. The disadvantage is that bee scouts basically lose information about sites they promoted. The advantage is that the bees as a whole do not waste too much time in endless debates.
Ants have a similar time lag, since ants who find good sites start recruiting and stop searching. In both bees and ants, the net result is that there is an optimal tradeoff between spending time on scouting versus decision-making.
Google uses searches to track flu's spread: 
- Biopedia  open-source bioinformation encyclopedia.
- Deborah Gordon digs ants  "With a dusty backhoe, a handful of Japanese paint markers and a few students in tow, Deborah Gordon digs up ant colonies in the Arizona desert in search of keys to understanding complex systems."
- Szu et al. (2004), Collective and distributive swarm intelligence: evolutional biological survey 
- Franks (1989) Army Ants: A Collective Intelligence