Honey Bees as a Superorganism

1. Honey Bees as a Superorganism University of Florida Department of Entomology & Nematology Dr. Jamie Ellis Created by: Jamie Ellis & Catherine Nalen

2. What do you know about honey bees?

3. What Do You Know About Honey Bees? • Honey bees make honey • Honey bees sting • Honey is bee “barf” • Honey bees pollinate crops • Because honey bees pollinate crops, we get fruits, nuts, vegetables, etc

4. What Do You Know About Honey Bees? • Honey bees communicate by dancing • African “killer” bees are honey bees • Worker honey bees can sting only once and die as a result • Honey bee colonies can contain up to 60,000 individual bees or more

5. Definition of an Organism: • DEFINITION 1: • an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent • 2. DEFINITION 2: • a complex structure of interdependent and subordinate elements whose relations and properties are largelydetermined by their function of the whole • Source: Merriam Webster’s Collegiate Dictionary

6. SO… • A single honey bee is an organism: DEFINITION 1: an individual constituted to carry on the activities of life by means of organs separate in function but mutually dependent • A colony is an organism???: DEFINITION 2: a complex structure of interdependent and subordinate elements whose relations and properties are largely determined by their function of the whole

7. The Entomological Concept of the Superorganism Wilson and Sober define superorganism as: “a collection of single creatures that together possess the functional organization implicit in the formal definition of organism”

8. What do organisms “do” or “have”? • Cell or tissue specialization and “rejuvenation” • Glands and secretions (endocrine and exocrine systems) • Gather and consume food • Respire (gas exchange – or “breathe”) • Excrete wastes • Thermoregulate • Communicate • Immune responses • Reproduce

9. In the Superorganism Concept: = =

10. Cell or tissue specialization and “rejuvenation” • Bees subscribe to age-related polyethism • In other words, bees of a certain age tend to perform a set of predictable tasks for bees that age • Bees progress through this series of tasks as they age and conclude their lives as field bees • Removing 1 cohort of bees causes bees in the hive to “fill the gap” • Much of this is controlled hormonally through feedback loops http://www.beesource.com/resources/usda/honey-bee-life-history/

11. Glands and Secretions (Endocrine and Exocrine Glands) • Endocrine glands release hormones directly into the blood for signaling INSIDE the body • Exocrine glands secrete their products into ducts that lead to the external environment for signaling OUTSIDE the body Major endocrine glands. (Male on the left, female on the right.): 1. Pineal gland 2. Pituitary gland 3. Thyroid gland 5. Adrenal gland 6. Pancreas 7. Ovary 8. Testis. Note: the Thymus (labeled 4.) is not an endocrine gland.

12. The “endocrine” system of the superorganism • Individual bee behavior is controlled, in part, by HORMONES which are produced INSIDE an individual bee’s body, released INSIDE an individual bee’s body, to produce a response in the INDIVIDUAL bee • However, bees also produce PHEROMONES which are part of the exocrine system of the individual bee but of the endocrine system of the superorganism, and elicit a colonial level response.

13. The “endocrine” system of the superorganism

14. Gather Food A circle with a 3 mile radius encompasses ~28 mi2 3 miles

15. Gather Food

16. Trophallaxis and “communal stomach”

17. Respiration (gas exchange – or “breathing”) • Bees station “fanners” on the bottom and sides of the nest cavity (inside), outside the entrance on the landing platform, and in the entrance hole • The side fanners circulate air inside the hive • The few entrance fanners determine the direction and flow of air into and out of the nest cavity • In one study, small honey bee colonies were shown to have 3 “breathes” per minute during the day and 0.4 “breathes per minute at night!

18. Excretion of Wastes

19. Thermoregulation Brood nest temperature typically does not fall below or rise ~95 F.

20. Thermoregulation

21. Communication 1. 2. • Waggle Dance • Round Dance Winston 1991

22. Immunity • The honey bee genome has been sequenced. One key finding is that individual honey bees have relatively few genes that code for immune responses • In fact, honey bees have fewer immune response genes than do fruit flies (the other insect with a sequenced genome)

23. Immunity Uncapping infected brood Physical removal

24. Reproduction Caron 1999

25. Superorganism Reproduction

26. Superorganism Reproduction

27. All Organisms Die…

28. When is a Honey Bee Colony Dead? • When the actual colony is dead? • When a colony swarms? • When a queen dies? • When the genetic information is lost (when is that)?

29. Is this a useful concept? If so, why?

30. “The bee colony superoganism is more than the simple sum of all its parts. It possesses properties that one does not find in single bees, although many of the properties of single bees determine and influence those of the entire colony, within the framework of its sociophysiology.” Jurgen Tautz – The Buzz about Bees, Biology of a Superorganism.