week 6 Flashcards
what are european honey bees considered
livestock
how many subspecies of honey bees
30
what are the differences between subspecies of honey bees
Different types of honey bees are good at different things
Think of dog species
Apis mellifera ligustica
Italian bees
Produce lots of honey
Apis mellifera mellifera
German bee
Good at overwintering
Not as much honey
Apis mellifera scutellata
African bees
no overwintering
defensive
what are some characteristics of european bees
Gentle
Honey producers
Good overwintering
Adapted to temperate climates
what are some characteristics of african bees
Defensive
Good at reproducing
No need to overwinter
Adapted to tropics
how and when did honey bees arrive in the americas?
17th century
colonizers brought
what was the indigenous perspective of stingless bees in americas
Stingless bees cultured in americas
Lots of influence in culture
what was the outcome of european bees being brought to the americas
Naturalized and established
Arguably not invasive
how/when did african bees arive in americas
Dr. Kerr brings apis mellifera scutellata from east africa to brazil in 1956
Tried to make more efficient bees
Ooops research went wrong
Swarm and Queens escaped
what was the outcome of african bees being brought to americas? where did they spread?
Changed apiculture and agricultural landscapes forever
Africanized bees take over
Move north through americas
Found in most of south and central america and in parts of US
Don’t know where they will go next
what are africanized bees and how are they made
Hybrids between european and africanized bees
European queen and african drone
European drone and african queen
what parent do africanized bees inherit defensive behaviour from? how do we use this to our advantage?
Defensive behaviour inherited from drones
Use this knowledge to control unwanted behaviour by saturating air with european drones
what does it mean for africanized bees to be defensive? what is the outcome of this
More reactive to alarm pheromone sting more than european bees
Run
Fly
Chase you
Walk
See threats very easily
public safety issue
Can’t have kids, animals around when harvesting
why is smoke used when beekeepers are handling africanized bees
Reduces defensive alarm pheromones
what does a stinger do when removed
rips out skin
dagger like
what does it mean to abscond? what type of bee is more likely to do this?
africanized bees
Queen and workers leave hive to find another nesting location
Causes
Diseases
Predators
Lack of forage
what does it mean to usurp? what type of bee is more likely to do this?
Swarm of africanized bees take over colony of european descent
Kill european queen and rear their own brood
what are some reasons africanized bees are harder to deal with for beekeepers
Defensive
Higher tendency to swarm
Abscond
Usurp
Lower honey stores
what are some reasons africanized bees are easier to deal with for beekeepers
Higher tolerance to disease
-ex. Veromites which Cause european bees to collapse
Better at defending from predators
Produce more propolis than European
-resins/sap from trees
-Use it to cover hive
- we use it to mummify
why do africanized bees have a higher tendency to swarm
Put lots of energy into producing more queens
how much more honey do european bees make compared to africanized
European honey bees produce 30% more honey than africanized
why do africanized bees produce less honey
Africanized workers have shorter foraging lives than european
Don’t have long winters so don’t need honey for winter
why are queens more likely to mate with africanized drones
africanized colonies produce more drones
how can you identify africanized bees?
Look the same as European bees
Stings hurt the same
Morphometric analysis
PCR (DNA)
SNPs
what systems does canada have in place to prevent africanized bee invasion
Can’t import queens into canada
What percent of insects considered herbivorous
35%
what percent of insects considered pests
1-3%
what is a pest
Insect that harms humans/livestock/crops/possessions
what are some types of herbivorous insects
Leaf feeders
Sap suckers
Leaf miners
-Bypass cellulose or unwanted layers of leaf
Stem feeders
Root feeders
fruit/seed feeders
are herbivorous insects always only bad for plants
no
nectar/pollen
Can be damaging herbivores when larvae, but beneficial pollinators when adults
have to weigh cost/benefit
are the actions of any individual in the population strictly have 1 effect
no, Food webs and networks
Very complex
Not just individual relationships
when did insects evolve in relation to plants
Insects first appeared at or before origin of vascular plants
Two most significant radiation in insect diversity coincide with evolution of
Seed plants (gymnosperms)
Flower plants (angiosperms)
how do insect herbivores affect the evolution of plants and vice versa
Plants have to evolve to compete with insects
Reciprocal interactions between plants and herbivores over evolutionary time shaped plants, insect and plant-insect interactions we now observe
-Plant defenses to reduce herbivory
-Insect strategies to overcome plan defenses
how does herbivory affect diversification of insects
Herbivory increases diversification of insects
More herbivory correlated with more types of species
what is coevolution
Coevolution = “evolutionary arms race”
Each trying to get upper hand on eachother
what is an example of coevolution
Plant evolves new chemical defense: temporarily free from herbivory
Radiation of new but related plant species
Insect evolves ability to overcome plant defenses: temporarily free from competition
Radiation of new but related insect species
Cycle continues over time
what are constitutive vs induced plant defenses
Constitutive defence
Always present
Induced defense
Synthesized in response to plant injury
what are some examples of mechanical plant defenses
Waxy epidermal cuticles
Leaf toughness
Seed coats
Spines, prickles, thorns
Bark
Trichomes
Pitching out
what are plant some trichomes
Hairs
Scales
Glandular - exude substances
-Sticky, annoying, toxic compounds
what is pitching out
Damage tree produces pitch
Resin that traps insects
what are primary metabolites in plants
Primary molecules important for life stuff of plants
Amino acids, sugars, nucleotides, lipids
Found throughout plant kingdom
Function in growth and reproduction
what are secondary metabolites in plants and what are they used for
(used for chemical defense)
Often co-opted metabolism by-products
Found in related groups of species
what are some of the functions of secondary metabolites in plants
Feeding and oviposition deterrents
Toxicants
Antimicrobial activity
Attractants (smell, color, taste) for pollinators and parasitoids
what re non-volitalie secondary metabolites and an example
Have to come into contact with
Ex. limonene
Can be distasteful to herbivores
what are volatile secondary metabolites and an example
Can be detected by predators before contact
Ex. menthol
Warns herbivores plant is toxic before feeding commences
what are Phytoecdysones
secondary metabolites
Plant steroids similar to insect molting hormones
Can interfere with molting when ingested
what are some examples of chemical defenses in plants
Glucosinolates only present in brassicaceae
Nicotine in tobacco
Tannins in tea and other plants
Salicylic acid (aspirin) in willow bark
Caffein, morphine, cocaine, cannabis, myrcene
how have butterfly species evolved to feed on plants with glucosinolate
Some species can feed on plants with glucosinolate
Some cannot feed
Some evolved to not have to feed
what are semiochemicals
chemical communication
what are allelochemicals and what do they do
Semiochemicals that facilitate inter-species communication
what are the 2 types of allelochemicals and what do they do
Allomones
Produce negative responses in insects
Repellents, deterrents, toxins
Kairomones
Produce positive responses in insects
Attractants stimulants, excitants
what is an example of a plant relying on allelochemicals
Say plant produces volatile chemical
Some insect feeds and releases allelochemicals
Allelochemical acts as kairomone and attracts more herbivores
Also attracts some predators/parasitoid that plant relies on for defense
Allelochemical might also act as allomone and repel herbivores for feeding and oviposition
what is plant eavesdropping
Herbivore-induced plant volatiles induce indirect defense in neighboring plants
what are some ways insects evolved do combat plant defenses
Morphological adaptations
Behavioural adaptations
Biological conditioning
Detoxification
Sequestration
Genetic resistance
Population level responses
give 2 examples of morphological adaptations insects use to overcome plant defenses
Acorn weevil
Evolved snout to get inside acorn
Horntails
Horned tail to burrow inside bark of tree
what is an example of behavioural adaptations insects use to combat plant defense
Eat parts of leaves to avoid or limit production of defensive compounds
Ex. trenching
what is biological conditioning and an example
Creates conditions where insect can better attack that plant
Ex.
Inoculation of plant with fungi (and bacteria) to alter/suppress plant defenses or improve plant nutrition for offspring
Mycangium
Structure on body adapted to transport spores of symbiotic fungi
how do insects use detoxification to overcome plant defenses
Detoxification enzymes
saliva Injected into plant tissues to reduce production of or break down induced compounds
what is an example of detoxification to overcome plant defenses
Parsnip webworm and wild parsnip
Webworm has ability to metabolize furanocoumarins
Corn earworm caterpillars feeding on tobacco plants
what is sequestration
Storage of toxic/distasteful secondary plant metabolites in tissues
what are some insects that use sequestration and why is it useful
Ex. turnip sawfly, milkweed bug, monarch butterfly all sequester cardenolides
Distasteful to predators
Reduce competition
Many with aposematic coloration
what is genetic resistance and an example
Mutations within genome to feed on a plant
18 insect species that feed on plants containing cardenolide poisons (milkweed)
All 4 orders of insects examined had amino acid substitution in same position of gene that allows them to feed on these plants
Substitutions occurred independently at least 4 times
what is the strategy of population level increase to overcome plant defenses
Overwhelm plant defense with enough individuals
give an example of population level increase to overcome plant defense
Ex. mountain pine beetle
When they identify group of pine
Produce aggregation pheromones
Tells mountain pine beetle to group together and attack specific trees
Trees can’t produce enough pitch to fight off all beetles
Is there a winner in the coevolutionary arms race
not really, they evolve new methods of getting resources or go extinct
what are some characteristics of solitary bees and wasps
Central place foragers
-Go out and search for resources and bring them back to nest
An established nest
Some resources
Limited defense
Typical solitary bee nest
-Single little tunnel in the ground
what is cleptoparasitism
Sometimes called Cuckoos
After cuckoo birds who lay eggs in other nests
Lay eggs in nests of other species
how common is cleptoparasitism (what percent of bees do it)
Very common
17% of bees
what are two possible origins of cleptoparasitism in bees
nest usurpation
Male structures
why might nest usurpation be a reason for cleptoparasitism in bees
Building a nest is tough
Easier to take over someone else
Some conspecifics (members of same species) will take over nest site
Sometimes members of another species take over
why might male structures be a reason for cleptoparasitism in bees
Brood parasites share characteristics with males
Absence of nest building and pollen collection structures
Searching behaviour
Structures for fighting (sometimes)
only takes 1 small genome to switch from male to female
how is sex determined in hymemoptera
Fertilized egg
Needs diploid female and haploid male
Makes diploid female
Unfertilized egg
Produced from diploid female
Produces haploid male
what is the relatedness of mother-offspring, father-daughter, sister-sister and daughter-granchild in haplodiploid insects
Mother - offspring = 50%
Father - daughter = 100%/50%
Sister - sister = 75%
Daughter - grandchild = 50%
who is more closely related in haplodiploid insects, mother-child or sister-sister?
what does this explain?
Sisters more closely related than their offspring
If you’re sterile you can still support your sisters to continue having offspring - social behaviour
what type of bee is eusociality most recent in
halictid bees
what do social insects do
Build nests
Accumulate resources on large scale
Powerful workforce
what order of insects is social groups most common in
hymenoptera
what is robbery in social insects
Raiding other nests for resources
Obligate raiders in the stingless bees
Lestimelitta (lemon bee)
cleptotrigona
what is social parasitism
one species exploits the social structure and behavior of another species, essentially “freeloading” off the host’s work by living within the host colony and relying on the host to raise its young, often without contributing to the colony’s upkeep
what species is social parasitsm common in
Common in bumble bees, sweat bees, allodapine bees and vespids
Social parasitic sweat bees
Allodapine bees
how long do social parasitic species live in host nest
Annual colony cycle
what do bombus (psithyrus) do that is socially parasitic
Social parasitic bumblebee
Don’t build their own nests
Just go into other nests and lay their eggs there
what is emerys rule
Social parasites are related to hosts
what is the strict form vs loose form of emerys rule? why is not always one or the other?
Strict form
Host and parasite are sister species
Closest related species (from same node)
Loose form
Closely related but not sister
Sometimes it started as strict form but switches to loose form or starts as loose form but switches to strict
Diversify, go extinct, switch host
what is slavery in social insects
Taking individuals from another nest
Using those individuals for your own purpose
what are slave making ants
Similar to social parasites and robbers
Queen acts like social parasite
How it reproduces and spreads
Gets into colony and takes over roll of queen
Slave making ant workers raid other colonies for workers (dulosis)
Slave maker Polyergus entirely dependent on host/slave Formica
