social evolution Flashcards
what do eusocial societies include?
give 2 insects and 1 mammal that are eusocial.
caste of sterile workers, either permanently or conditionally
2 insects:
- ants/termites
- bees/wasps
mammal: naked mole rats
define eusocial
a social system where cooperative care of young and a reproductive division of labor occur within multigenerational group
a colobopsis ant ruptures its abdomen spilling toxic goo onto enemy, killing both enemy and itself. this demonstrates that eusocial insects usually do what?
eusocial insects display altruistic self-sacrifice in many cases, to defend nest and social group
what is altruism?
hurting yourself to help others
inndividual vs group selection
Group selection – Groups that have altruistic behavior are more likely to survive than groups lacking altruistic individuals.
Individual selection – Individuals that are better at surviving and reproducing are more likely to pass on their genes, even if it means acting in their own self-interest.
which selection, group or individual, has much stronger effect on evolution than the other?
individual selection
natural selection can act on 3 levels. what are they?
between groups within a population
between individuals within a group
between genes within an individual
what is direct and indirect fitness? what about inclusive fitness?
direct fitness - measure of reproductive (genetic) success based on number of offspring that live to reproduce
indirect fitness - measure of genetic success of an altruistic individual based on number of relatives that they help to survive and thus reproduce
inclusive fitness - measure of individual’s total contribution to genes (direct + indirect)
______ are similar to jellyfish and includes the man of war.
they are not a single organism, but comprised of multicellular _____ with different functions.
operate much like a _____ insect colony.
siphonophores
zooids
eusocial
slime mold - the social amoeba
this amoeba is a ______ that cooperates and behaves altruistically towards ________
during food _______, they aggregate into ______
they form _____ stalks with a _____ body
only the amoeba in the ______ reproduce while the ones on the stalks are _______ so they can better disperse the spores
protozoan; relatives
scarcity; slug-like colonies
reproductive; fruiting
fruiting body; altruistically supporting them
portuguese man of war has a gas filled float that plays a role in positive buoyancy and used as a sail to catch wind. what’s this structure called?
pneumatophore
the only zooid that ingests food, unigue to the man of war, is called?
gastrozooid
a polyp that has tentacles, unique to man of war. what’s it called? what’s it for?
tentacular palpon
to capture prey
specialises in nermatocyst production
this is a structure in the man of war that is released from the colony of zooids when they mature. it is ________.
gonodendron. it includes:
1) gonophore - medusa containing female/male
2) palpon - derived gastrozooid
3) nectophore - medusa used for locomotion
4) jelly polyp - reduced nectophore, function unclear
hymenopterans (wasps, bees, and ants) have ___________ males which have ____ set(s) of chromosomes instead of ___. this means they have ___ allele(s) at each genetic loci. (females are diploid)
males are produced via __________ from unfertilised eggs (they only inherit mtoher’s DNA). this makes ______ in the same generation more related to each other compared to other species.
haploid; 1; 2; 1
parthenogenesis; females
what is the haplodiploidy hypothesis?
relatively higher relatedness of full sisters in haplodiploid populations promotes altruism among siblings and consequently, the evolution of eusociality
does the haplodiploidy hypothesis fully explain eusociality?
no