Amateur Naturalist: Is The Red-Winged Blackbird A Superorganism?

View of 100+ red-winged blackbirds waiting for dinner at the top of a tree. Photo by Robert Dryja

Los Alamos

The individual members of an insect colony may become like a multi-creature organism when they come together. Honey bees are an example. A single bee may find a tree in bloom and is able to collect some nectar. When it returns to its hive, it performs a kind of dance, telling other bees where the tree is. The result is hundreds of bees going to that tree and confirm it is a good source of nectar. 

Bees work as group in their colony to build combs of beeswax. The beeswax is built into hexagonal tubes to store honey made from flower nectar. Alternatively, a vast nursery for eggs may be laid in a comb by the queen bee and the larva then are fed by the worker bees.

During the winter the bees gather into a ball. The bees generate heat by vibrating their wings and this heat is at the center of the ball. Individual bees move repeatedly back and forth from the cooler outside to the warmer center. The bees therefore survive rather than be frozen in the winter.

Together they show more intelligence and adaptability than any one member. Together they can gather all the nectar from a tree, know where to go, and when all the nectar has been collected. They decide how large a wax comb to build and where in a nest to place it. They decide which section of a comb to use for honey storage which section to use for raising young bees. They monitor and maintain the correct temperature inside a ball of bees during the winter. These are all behaviors that a single bee could not do on its own. A colony can be considered to be a superorganism, not just a gathering of individual bees.

Do superorganisms exist elsewhere, such as among birds? The red-winged blackbird is an example.  Red-winged black birds often are thought of as living in marshy areas or by ponds to raise their young.  They are disbursed in such areas. Something different occurs during the autumn and winter months.  Hundreds or even thousands may gather in flocks and live among the grasslands and forests of a mountainside, far away from any mash or pond. They will return to mashes and ponds when spring arrives. Their behavior suggests they now are acting as a superorganism.  

A flock may gather in a particular tree during an autumn day. It may be the tallest tree without leaves in an area. Why did the flock decide on the tree? Is it a good reconnoitering point? A solitary bird may act like a single bee finding a good source of nectar. The solitary bird finds an abundant source of food and reports back to the flock. The flock then takes off as a group and goes to the food source. A bird feeder in a yard may suddenly be covered by the birds. The flock then takes off together when no more food remains.

Red-winged blackbirds having dinner at feeder tray. Photo by Robert Dryja

The flock returns to its starting tree after feeding. However a different kind of tree is preferred for the night time. Where do they decide to go at night? A pine tree with its needles can provide coverage from cool breezes and a place to hide. The flock is now acting like a ball of bees looking for protection from the weather. A person can walk by a tall pine tree in the late afternoon and hear a cacophony of sound but not see a bird. They leave in the morning for a food reconnoitering tree.  

Some sort of group intelligence is at work when flying. One would expect single birds or small groups to leave the flock if decisions were made individually. Instead, a group takes off or lands together. The group somehow decides in which direction to fly, when to fly in long curves, or fly up and down.

Computer programs are available that model flocking behavior. Images of moving birds on a computer screen come together in flocks. However the direction of the flocking movement is randomly generated and is in two dimensions on a flat computer screen. Red-winged blackbirds instead are flying with a group purpose and in the three dimensions of space.