Transcript Advanced Bee Biology

Bee Genetics
Clarence H. Collison
Emeritus Professor/Dept. Head
Mississippi State University
3 Components To A
Productive Colony
High Quality Queen
Large Nurse Bee Population
Large Foraging Force
The Queen’s Genetics Plus
Drones She Mates With
Determines:
Colony Temperament
Colony Size
Productivity
Beekeepers evaluate queens
on basis of colony
characteristics:
•
•
Brood pattern
Behavior of the queen on
the combs
• Temperament of workers
• Production records
A queen controls
fertilization by regulating
the release of spermatozoa
from her spermatheca.
Her entire supply of
spermatozoa is limited to
those obtained before she
starts egg laying, so she
must dispense them
gradually.
Several spermatozoa are
apparently released each
time a fertilized egg is laid,
but the actual depletion rate
is unknown.
Colony traits change due to
different matings.
Sperm clump and form layers
in the spermatheca.
Needs to be considered when
judging a queen.
The Average Drone
Produces About 8
Million Spermatozoa
The Average Queen
Receives 50 Million
Spermatozoa During
Her Mating Flight
Queen’s spermatheca
normally contains 5-7
million spermatozoa.
Queens with sperm
counts less than 3
million are unable to
head colonies for one
season.
Drones are sexually mature at
approximately 12 days of age.
Sperm count goes down after
20 days of age.
All Sperm Produced
By A Drone Are
Genetically Identical
Sperm May Remain
Viable In The
Spermatheca Of A
Queen For At Least
Three Years
Queens Become
Sexually Mature About 5
Days After Emergence
May Become Drone Layers If
Bad Weather Keeps Them
FromTaking Mating Flight(s)
For Over 20 Days
(Lose Urge To Mate)
Queen Mating Flight
 1-2 Weeks Old When She Goes On Her
Mating Flight(s)
 Almost Always Mates In The Afternoon
 Circles Hive Several Times To Orient To
The Location Of The Hive
 Flies Low To The Ground, Less Than 15
Feet High To Get Away From The Hive
Area (Believed To Prevent Inbreeding)
Altitude Of 20 To 100
Feet Is The Only Area
Where Drones Will Be
Attracted To Her
Queen Mating Flight II
 Flies A Long Way Before Going Up




In The Breeding Altitude
Mates With 7-15 Drones
Mates With A Drone Every 2-5
Seconds
Gone From The Hive About 13
Minutes
Has A Combined Flight Range Of
About ½ To 1 Mile
40% Of Queens Mate On First
Flight
May Take 2nd or 3rd Flights
Post-Mating Behavior
 Queen Begins To Lay Approximately 48
Hours After Mating Flight
 Once Egg Laying Begins, A Queen Will
Not Mate Again
Drone Congregation Areas
Drone Congregation Areas I
 Drones congregate in definite areas
outside the hive.
 Follow definite flight lanes as they
approach these areas.
 The same congregation areas are used
year after year.
Drone Congregation Areas II
 Generally all drones visit a given
congregation area in the vicinity of the
hives.
 Drone congregation areas vary in size.
 Boundaries marked by a vertical relief
(trees, building, hill etc.)
Drone Congregation Areas III
 Drones fly at about tree top level.
 When they reach a point marked by a
clearing among trees, an open hollow
or a slight summit, they assemble and
wait for a queen.
 Normally fly between 11:00 a.m. and
4:30 p.m.
Since A Queen Mates With
Several Drones Some Of
Her Daughters Have
Different Fathers And
Some Share The Same
Father
Super-Sisters- Share An
Average Of 75% Of Their
Genes
Half-Sisters- Have About
25% Of Their Genes In
Common
Queens Must Mate
With Unrelated
Drones To Get
Different Sex Alleles
Queens Sometimes Lay
Inviable Eggs Because
Of A Single Gene
Resulting In A Shotgun
Brood Pattern
If A Queen Is Mated To
A Closely Related
Drone, She Is Likely To
Produce Scattered
Brood
There Are
Approximately 20
Different Sex Alleles In
The Honey Bee
Population, All Of Them
At Approximately Equal
Frequency
A Larva That Has Two
Different Sex Alleles Will
Develop Into A Normal
Female (Worker Or
Queen)
A Larva That Has Two Of The
Same Sex Allele Will Develop
Into An Abnormal Male
(Diploid Drone)
Diploid Drone Larvae Are
Eaten By Nurse Bees When
They Are Less Than A Day
Old, Leaving An Empty Cell
Because Of This Problem
With Identical Sex Alleles, It Is
Important That Queens Mate
With Drones With Different
Genetic Backgrounds
Mating Has Permanent
Effects On Queen
Behavior, Physiology
And Resultant QueenWorker Interactions
(Richard et al. 2007)
Mating Stimulates
Vitellogensis (Formation Of
Yolk Protein) And Oocyte
Maturation (Egg Formation) In
The Ovaries Which Prompts
The Initiation Of Egg-Laying
(Tanaka & Hartfelder 2004)
Mating Alters The Pheromone
Profiles Of Queens Allowing
Them To Regulate Many
Different Aspects Of Worker
Behavior And Colony
Organization
Insemination Quantity
Significantly Affects
Mandibular Gland Chemical
Profiles, Queen-Worker
Interactions And Brain Gene
Expression
(Richard et al. 2007)
Virgin Queens Were
Compared To Single Drone
Inseminated And Multiple
Drone (10) Inseminated
Queens
Multiple Drone Inseminated
Queens Elicited A Stronger
Retinue Response Than
Single Drone Inseminations
It Takes Numerous
Drones To Fully
Inseminate A Queen
Clear Direct Benefits
Of A Queen Mating
With Multiple Drones
(Tarpy 2003)
A Fully Filled
Spermatheca Results
In A Longer EggLaying Life Span
Increases The Likelihood Of
Having A Sufficient Supply Of
Stored Semen And Lower
Probability Of Inbreeding
End Up With A Variable And
Cosmopolitan Worker
Population
Queens That Mate With Many
Drones Will Ensure That
Some Of Her Workers (half on
average) Will Inherit
Favorable Alleles From Their
Father
A Queen That Mates Only
With A Single Drone Runs
The Risk Of Carrying Alleles
That Are Susceptible To A
Particular Disease
Queens That Mate With
Multiple Drones Ensure At
Least Some Of Her Workers
Will Be Resistant To The
Disease
Any Trait Could Be Impacted
By Increased Genetic
Diversity Within The Colony
As A Result Of The Queen
Mating With Multiple Drones
Beekeepers Need To Be Sure
That Their Queens Are
Properly Inseminated With A
Generous Assortment Of
Drone Genotypes So That The
Worker Population Is
Similarly Variable
There Are Indirect Benefits Of
Multiple Matings For Colony
Health And Productivity
Drones Carry Different Genes
For A Wide Variety Of Traits
When A Queen Produces
Worker Offspring Sired By
Different Males, The Workers
Vary From Each Other
Genetically
There Are Biological
Advantages To Queens
Mating With Multiple Drones
Providing A Genetically
Diverse Worker Force
More Stable And Resilient
Division Of Labor
Genetic Task
Specialization
Higher Genetic Diversity
May Enable Colonies To Extract
Resources From The Environment
More Efficiently
Brood Nest Temperatures Are More
Stable
Reduces Susceptibility To Various
Pathogens and Parasites
Genetically Diverse Swarms
Established New Colonies
Faster
Built More Comb
Had More Frames Of Brood
Higher Foraging Levels
Higher Weight Gains
Genetic Diversity
Increased Colony Fitness
Disease Resistance
Greater Productivity