Ants At Work by Deborah Gordon

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Ants At Workby Deborah Gordon

• Paige Johan
• Anthropology 179A
• Dr. White
• UCI Fall 2002

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Various Networks of Ants

• Networks and connections within the ant colony.
• Networks of trails and paths to food outside the
  colony.
• Networking and connections with neighboring ant
  colonies.

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3 Distinct Levels of Ants

• Queen Ants
• Winged
• Only ants that can reproduce females
• Male Ants
• Winged
• Life Span Only a few weeks
• Only live for reproduction
• Sterile Female Ants
• Worker Ants
• Can reproduce males (do not need sterilization)

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Life Cycles

• Colony Life Cycles
• Form when a New Queen mates with a Male from
  another parent colony, and then forms her own
  colony
• Generally last about 15 years
• Can exist as long as the Queen can continue
  reproducing female workers
• Individual Ant Life Cycles
• Queen 15- 20 years
• Males A few weeks (long enough to reproduce)
• Female Workers About 1 year

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Working Ants and Daily Chores

• Interior Workers
• Tend to the Queen and brood (eggs, larvae, and
  pupae)
• Nest Maintenance
• Open and close entrances to the nest
• Maintain all structures and pathways within the
  colony
• Patrollers
• Designate the foraging paths for the day
• Foragers
• Follow paths designated for them to gather food
  for the colony
• Midden Workers
• Manage the refuse pile, also known as the Midden
• The Midden also seems to have a significant
  relation to how the ants find their colony.

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Allocation of Tasks

• No source of leadership
• Queen is only there to reproduce, not to control
  the colony
• As conditions change emphasis on certain jobs
  change
• Workers are moved from one task to another
  depending on the need for workers
• Ex. If there are serious issues with nest
  maintenance, some foragers will switch to nest
  maintenance until the problem is solved.
• Foraging is the most important task and will call
  for workers before any other task

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Foraging Paths and Trails

• Mature colonies can have up to 8 customary
  foraging trails
• However, patrolling ants generally do not send
  foraging ants to the same trail as the day before
• Younger colonies are more likely to send their
  foraging ants to a rich food source they had once
  found

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Foraging Paths (continued)

• Larger colonies dont necessarily cover larger
  areas, but get more food because they have more
  workers
• Paths are very adaptable
• They grow into more intricate paths with the
  growth of the workforce
• A small workforce changes the paths to a more
  standard construct to cover area more effectively

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Connections with Other Colonies

• Workers can recognize ants from their own colony
  by a colony specific scent
• When foragers from different colonies meet, those
  foraging trails will be used less and less, and
  seen as space lost to competition
• Certain foragers specialize in fighting, and are
  usually not let out unless large number of
  foragers are out

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Older Colonies vs. Younger Colonies

• Older colonies are more likely to interact with
  other colonies
• Colonies remain about the same size
• Once colonies reach the 2-year mark they are
  likely to keep the size of their nest the same
• More ants are sent out from the older colony
• Older colonies also send their foragers out
  farther distance

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Natural Response to Strangers

• Ants respond to the rate of interaction with
  non-nestmates
• Sight not good, use contact rate to determine the
  density of non-nestmates
• Ants will try to maintain density through
  clustering when they feel contact rate is low
• Contact rate directly correlates with density of
  nestmates
• Low contact rates indicates high numbers of mates
  present
• High contact rates indicate low number of mates
  present

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Sources Used

• Gordon, D. (1999). Ants at work. New York, NY
  The Free Press.
• Foster, D. (2001) An ants life. Retrieved from
  the World Wide Web on November 13, 2002.
• Library.Thinkquest.org. (?). Insects. Retrieved
  from the World Wide Web on November 13, 2002.
• The University of Georgia College of Agricultural
  and Environmental Sciences. (2000). Managing
  imported fire ants in urban areas. Retrieved
  from the World Wide Web on November 13, 2002.