Final Flashcards
Batesian Mimics
Non toxic species that behave as through they are toxic or dangerous. Only works if there are species in the environment that are dangerous or toxic so the predator is aware of the threat.
How can animals at consumption still fight back
Using sticky, noxious, smelly secretions (from diet or produced)
Sawfly Larvae
(Wasp ish baby)
Wats eucolyptis and has glands of it which they spit out as droplets of repellant oil under attack
Selfish herd
Penguins will push others to edge of ice so a few are sacrificed to leopard seals and so the rest can swim on by
How do musk ox fight back
Gather in groups with horns out, safest spot is the middle with calves
Misdirecting attacks
- geckos bright colours of tail can break off and keep predator busy and grow new no bone tail
- catacola on wings
Rabbit last attempt to survive
Fat head minnows last attempt
Attracts competent predators to create chaos during which they can escape.
-fear screams
Release chemical to attract pike to fight other pike (allomone)
Dimorphism
Polymorphism
2 forms
Many forms of male and female looks
Handicaps of trying to get females attention
- attracts other males
- attracts predators
Bowerbird
Dimorphism of male and female
- males construct a bower, hallway of twigs and decorations to show off
- females come to inspect bowers and compare them based on bower, singing, plumage and dancing.
- accepts by entering bower and crouching down
Why build bowers
Indicate relative male quality brain power
Bower=extended phenotype to show strength
Bower birds have larger brains than non bower birds
Super studs
A select few males that get all the matings
-others get few or non
High variance of individuals in the _____ sex and low variance in the _____ sex
Competing
Choosey
Eggs are
Sperm are
Expensive: large, produce less, matters if reproduction doesn’t work
Cheap: small, produce lots, doesn’t matter if reproduction doesn’t work
OSR
Operational sex ratio
The number of available mates of one sex relative to the other sex at a given time and place. Usually male biased-more males around trying to mate than females.
(Not total population, but a portion)
Parental investment
Resources (energy, time..) devoted by a parents to the successful reading of current offspring that come at the expense of future offspring
Rate limiting sex characteristics
- higher parental investment/ donations
- low potential reproductive rate (less time to search for mate)
- low levels of sexual activity
- selection among mates
- All about resources and quality
- choosey
- less available to mate
Male biased or competitive sex
- lower parental investments/ donations
- high potential reproductive rate (less time with offspring)
- high levels of sexual activity
- competition for mates
- the more mates the higher the individuals fitness
- are in excess
- quantity is key
Female long tailed dance fly
- Display for males
- males are good hunters and catch prey
- females need prey to reproduce
- male offers it as nuptial gift to whom is fit
- females compete in swarms, bigger is best
- more females than males
Female bias
Seahorse
And male fish
Brood pouches for developing fertilized eggs
- only so much space in brood based on size (rate limiting)
- males very choosey and evaluate females
Males usually provide parental care
Female Morman cricket
Males produce spermatophore which is highly nutritious and helps reproduction in females.
- males choosey with who gets
- more females looking for a good spermatophore (compete)
- males weigh females and reject small ones
Katydid
1 season males are biased and others females are
- dry season: males can only eat kangaroo-pow flower so takes longer to make spermatophore
- wet season, more pollen around so easier to make spermatophore so females are less and choosey
Male dung beetle
Big horns are good for fighting but make their eyes small
Large eyes and no horns are good for seeing predators and these have larger testis. However must sneak in to mate because females like big horns
Polymorphism not genetically different
Secondary sexual traits that produce more offspring even if lower lifespan will
Always be selected for
Sexual selection
The advantage which certain individuals have over others of the same sex and species that in exclusive relation to reproduction
Two components of sexual selection
Intersexual interactions
-within sex (competition)
Intrasexual interactions
-outside sex :female and male (choosy)
Costs of establishing dominance
- injury
- lost feeding time
- lost mating oppurtunities (small males might sneak in)
- dish of predation
Dominance hierarchies
-take time and energy to establish at first but after…
- reduce conflict
- result in greater mating opportunities for alphas
Monopolize dominance
Groups of baboons with most dominant males spend most time with females
How do lower males get time with females
- helping behaviours in exchange for sex
- coalitions to promote shared paternity, usually two young males without big size to fight will be able to drive off larger male, both copulate, 1 fertilizes
- May take care of offspring so once female is ready to mate they are there (helping)
Satellite males and example
Males that hang out in the area in hopes of getting a chance to fertilize
Small male iguanas pre ejaculate into penis to quickly transfer spermatophore before large males remove them
Minor and majors
Minors are smaller and look like females in dull colours
Majors are larger and come in bright colours due to better nutrition
Minors will hang out by females without major males being aggressive and sneak in fertilization
(Not genetic)
Satellite males and frogs
Frogs are external fertilizers so males may fertilize a female from a distance still (not competitive)
Horseshoe crab
During reproduction females goes to shallow water and lay eggs. Males follow along use claws to attach to fame shells, most fit males ride their way to shore and fertilize first. More success
Older males wait at shoreline
Male scorpion flies
Have different competitive abilities
- Hunt prey (nuptial gift) (60%)
- salivary secretions (females feed a little on it) (20%)
- force compilations (10%)
If dominant is removed each moves up a rank
Conditional strategy
Unequal reproductive success among polymorphism (big males reproduce more)
Behavioural plasticity
Ability to behave differently (not genetic, based on competition around)
Paracerceis sculpta
Similar to pill bug
Have genetic behavioural variants
-large males dominate sponges and females by ejecting other alphas or gammas if detected, alphas use cerci to control access to a female but not more, used for fighting
-betas behave like females and sneak copulations
Genetic polymorphism
- equal reproductive success
- locked in behaviours
Ex: pill bug things
- Alphas are large and fight for females
- betas are smaller, act like females
- gammas smallest can hide well
Antlers
Used to size up risk of competition
- antler flies: measured eye length of equal will fight
- antlers of bull moose and elk
How could fighting to death help reproduction
- May fight to death to protect copulation of other males (protect paternity)-get sperm in before fertilization
- usurping paternity (females store sperm for a little while)
Extreme violence is
Rare in animals
Accessing helps
Bulk elk video notes
Use tongue to taste air and volatiles of female hormones
-Calls are honest signals to other males of size and location and to announce to females, helps to avoid fights
Vomeronasal Gland
Inside upper lip of most mammals (male), stuck tongue to lip to detect female hormones
Doe’s testing
Females walk away from males and zig zag back and forth and males follow. Females tease and try and see how persistent the males are… does he have energy?= better mate
-females have control which drive evolution of male traits (coevolutionary)
Resource holding potential/ Power (RHP)
Ability of an individual to control access to a resource
Damselflies
Don’t fight directly, have rituals
Bigger is usually better but not always, # of prolonged aerial displays won by males for competing for territories
Energy reserves make the difference (mg of fat for food)
-most winners are not necessarily larger but have longer reserves of energy
Benefits and costs of testosterone
- promotes sperm production
- activates sexual behaviour
- stimulates aggressive behaviours (+ and -)
- suppressed immune system (get sick more often)
Elephant Musth
High testosterone level in blood that lead to aggression
- if two fight without musth, bigger wins
- if smaller is in musth they may overtake bigger
-fan wars, stream temporal gland oil on head, territorial, risks to ground movement
- last short periods of time so bulls don’t kill themselves
- sometimes direct aggression to females or young by mistake
Time spent in territorial contests takes time away from foraging example
Males implants with testosterone spent more time displaying than other males.
-survival cost of extra activity could be offset with a food supplement
Yellow spiny lizard
More males display in the morning, less active during heat of day
-augmented males display even in heat
-if extra testosterone with food left in territory it enhances survivorship
Supplement but no food = more deaths due to too much time spent displaying than foraging
Quality of wintering territory can affect reproductive success
America redstart fly south for winter. Need large fat reserve to make trip and insect production is high in Canada and US.
Don’t leave until fat reserve large enough, first time arrive have best pick of spot, males arrive first and fight for territory. Want mangrove trees for insects. Those that eat more from better locations leave earlier back to North and get better breeding territories.
In winter aggression between males and females is equal. In breeding ground males compete for females. Cost of not getting good location in winter is greater for females and they have less babies
Female dunnocks
Compete for male resources within a territory especially if they are in a polygynous group
More than one female to one male means females compete for male attention to get male to being food for her babies. =females with more testosterone and aggression
Monogamous= loser testosterone and less aggression in females
Who wins territorial contests
Residents usually
Older males may fight harder than younger males even if younger are more fit, because already been successful so they’ve won so less cost of dying
Dear neighbour/enemy effect
Separate individuals may work together to establish a territory, once boundaries are set aggression goes down lot. May even cooperate to repel invaders
Speed storage
Why might a female mate more than once if sperm are in excess
- First sperm obtained may not be viable
- Other spent may be better
- Access to resources
Blackwing damselfly
- males remove rivals sperm before transferring own
- females distribute eggs all over to stop nymphs from competing and eating each other
- rotates penis (aedeagus) with spiny thorns and pump to remove rival sperm. 95-97% effective
Mateguarding- males hold onto females until she has laid eggs in his pond
Males may hang around and forgo other matings to guard paternity when
Opportunities are hard to achieve and of competition is stiff
Mate guarding can include
- remaining physically with female
- Behaving like a female and inducing other males to mate
- inserting a plug or chemical that renders her incapable of receiving sperm or unreceptive to (hormonal)
Female birds anatomy permits choice
Have tubules of sperm storage in uterus lining.
Extra pair copulation
Copulation outside the social pair-bond
Timing of copulations relative to fertilization can allow females to control paternity
Females paired to suboptimal males can still mate with better males but males may boost sperm numbers in high competition
Females may get help fro both social mate and EPC in raising
Females more likely to mate with EPC later in breeding season
Evolution of stimulating male genitalia
Moneys: sharp penis makes females sore and sensitive and less likely to copulate soon again
-May have structure to remove other sperm
Male sparrows
Territories near food keep females near by and less likely to go off and meet another male
EPC chicks increase 3x in territories without food near by
Sexual suicide
Redback spider
Female is less receptive afterwards if she gets to eat the male
- males give up life as meal because it increases chance of fertilization and decreases chance of other mating opportunities
- males take out spermatophore out of genitalia with mouth and out into female genitalia and his body becomes a plug and she eats him
- excess of males and low females
Ways females tend to attempt to control reproductive decisions
- egg investment: what materials, and how much in each egg(add more into better male eggs)
- mate choice: which can be sperm donors
- egg fertilization: which sperm is used
- offspring investment: how much maintenance and care goes to each embryo and offspring (May favour)
Ways in which makes attempt to control reproductive decisions
- resources transferred to female: influence egg investment, mate choice, or egg fertilization decisions of female
- elaborate courtship: May influence mate choice
- sexual coercion: may overcome female preference for other males
- infanticide: speeds up for males, males females receptive sooner
Pairing behaviours
Monogamy- 1 male and 1 female
Polygamy:
-polyandry: 1 female and many males
-polygyny: 1 male and many females
-polygnandry: more than one female and more than one male
(Pair bonded all together, hippies)
polygyny
Polygyny is most common because in more species than not males have evolved to escape parental care obligations
Hedge sparrows
Can be paired in all these behavioural pairing
Monogamy is adaptive to
Polygyny is adaptive to
Females
Males
Variation in mating system behaviour can be explained in 4 ways:
- how much reproductive success is increased/ affected by male parental assistance
2. The size of female ranges
3. The size and stability of females social groups if they exist
4. The density and distribution of fertile and receptive females in space and time (long breeding seasons or short or all receptive at same time?)
Males sometimes are selected to anticipate which resources are important for female reproduction success and thus
Control those resources to influence female mate choice
Where are females and males
Females go where the resources are, where predation drives them and where their is a benefit or cost of social living, males go where females go or where resources females need are
