Honey Bee Development and Caste Determination Lecture

Flashcards covering honey bee development, caste determination, and roles of different castes derived from lecture notes.

Honey bee development stages

All individuals pass through the same stages: egg, larva, pupa, adult.

Egg (honey bee development)

The first stage of development, laid by the queen in a wax cell.

Larva (honey bee development)

The second stage of development, hatched from an egg and fed by worker bees.

Pupa (honey bee development)

The third stage of development, where the larva transforms inside a sealed cell into an adult bee.

Adult bee

The final stage of development, emerging from the cell after pupation.

Juvenile Hormone (JH)

Produced by the corpora allata, it controls development in the larval and pupal stages; high JH leads to larval molts, low JH to pupation, and no JH to adult emergence.

Ecdysone

Produced by the larval prothoracic gland, it controls molting in the larval and pupal stages.

Corpora allata

Gland at the base of a larva's brain responsible for producing Juvenile Hormone (JH).

Prothoracic gland

Gland in the larva that produces ecdysone.

Queen development time

Averages 16 days from egg to adult.

Worker development time

Averages 21 days from egg to adult.

Drone development time

Averages 24 days from egg to adult.

Drone (honey bee)

Male honey bee, haploid (n=16 chromosomes), no labor for the colony, mates with virgin queens and dies after mating.

Worker (honey bee)

Female honey bee, diploid (2n=32 chromosomes), performs all colony labor including foraging, feeding brood, and maintaining the hive.

Queen (honey bee)

Female honey bee, diploid (2n=32 chromosomes), whose sole job is to lay 800-2000 eggs per day and influence colony organization through pheromones; only one per hive.

Haploid

Possessing a single set of unpaired chromosomes; characteristic of male honey bees (drones).

Diploid

Possessing two complete sets of chromosomes; characteristic of female honey bees (queens and workers).

Drone behavior

Sexually mature by day 12, takes orientation flights, mates with virgin queens in drone congregation areas (DCAs), and dies after mating; often culled in temperate climates before winter.

Drone congregation area (DCA)

An area where drones gather to mate with virgin queens.

Queen behavior

Lays 800-2000 eggs per day, groomed and fed by workers, and influences colony organization via pheromones.

Worker activities

Include handling food, making honey and bee bread, feeding brood, capping brood, tending the queen, making combs, controlling temperature and humidity, guarding the colony, gathering resources, and cleaning the hive.

Trophallaxis

The mutual exchange of liquid food among colony members, used by workers to share resources like pollen.

Bee bread

A mixture of pollen, nectar, and enzymes, stored in cells and serving as food for larvae and adult bees.

Genetic basis of sex determination in honey bees

Males (drones) develop from unfertilized, haploid eggs, while females (queens and workers) develop from fertilized, diploid eggs; determined by the csd gene, not sex chromosomes.

Fertilized egg (honey bee)

A diploid (2n) egg that develops into a female (worker or queen).

Unfertilized egg (honey bee)

A haploid (n) egg that develops into a male (drone).

Environmental basis of caste determination (female honey bees)

The diet during larval development determines whether a female larva becomes a queen or a worker; continuous feeding of Royal Jelly leads to queen development.

Royal Jelly

A special secretion fed exclusively to queen larvae throughout their development; high amounts of this high-quality food drive queen determination.

Worker Jelly

Primarily hypopharyngeal gland secretions, fed to worker larvae after their initial 1-2 days of life.

Royalactin (MRJP1)

A protein in Royal Jelly initially thought to be the primary substance responsible for queen determination.

10-HDA (10-hydroxy-2-decenoic acid)

A fatty acid in Royal Jelly identified as a likely candidate compound contributing to queen determination.

Epigenetic modifications

Changes to DNA (like DNA methylation) or histones that modify gene expression by turning genes ON or OFF, affecting developmental trajectories based on diet.

DNA methylation (honey bees)

An epigenetic modification of DNA that plays a role in caste determination by altering gene expression.

Histone modifications (honey bees)

Epigenetic modifications to histones that contribute to caste determination by affecting chromatin states and gene expression in larvae.

Queen cell

A larger, specially constructed cell where a queen larva develops, receiving an exclusive diet of Royal Jelly.

Supersedure cell

An emergency queen cell built in the middle of a frame, often from a worker larva, when a colony needs to replace its queen.

Swarm cell

A queen cell built at the bottom of a frame when a colony is preparing to swarm.

Window of queen determination

A critical period of about 3 days post-hatching during which a female larva’s developmental trajectory can be switched from worker to queen.

Queenless colony

A honey bee colony without a queen, leading to worker ovaries developing, laying unfertilized (haploid) eggs, and producing only drones.

Brood pattern in queenless colonies

Characterized by an irregular pattern of drone-sized cells with raised caps, often at the outer edges of frames, resulting from worker-laid, unfertilized eggs.

Worker eggs in queenless colonies

Workers can lay unfertilized eggs in the absence of a queen, but these will only develop into drones as workers are unmated.