In finding the answers to today's clue you learned about two interesting mechanisms found in nature: the waggle dance and quorum sensing.
While today's clue focused on some insects who use this mechanism, it is found primarily in bacteria.
Quorum sensing was discovered by Kenneth Nealson, Terry Platt, and J. Woodland Hastings in 1971. In bacteria, this mechanism involves three components:
- a signalling molecule all members of the population secrete to allow identification of their presence,
- an autoinducer which can detect changes in concentrations of the signalling molecule, and
- a way to alter gene expression based on the concentration detected. This allows the bacteria to exhibit a property (phenotype) that best benefits the population density it is living in.
A fun example of quorum sensing is in bioluminescence, and this is also how the phenomenon was discovered by the scientists. They observed that the photoluminescent marine bacterium Aliivibrio fischeri did not synthesize (create) luciferase in fresh culture, so they did not glow. You'll remember luciferase as the bioluminescent component we learned about previously. The bacteria only glowed after the bacterial population had increased significantly - only after the population was dense enough. Learn more about quorum sensing, and why the bacteria Aliivibrio fischeri only glow in high density situations, below:
The second part of this clue looked at the famous waggle dance from honey bees. This movement involves having honey bees move in a squiggly line along a vertical line on the hive. The length of the squiggly line corresponds to the distance the food is from the nest and the angle away from a directly vertical line, is the angle the food is from the sun. Isn't that neat!
To learn more about the waggle dance have a look on wikipedia