BIOB50 Chapter 7 Review

11 Pages
Unlock Document

Biological Sciences
Marc Cadotte

BIOB50 Ecology Chapter 7 Life HistoryNemo Grows Up A Case Studyoffspring produced by different organisms varygrass plants produce seeds that are buried in soil until conditions are right for germinationsea star produces thousands of microscopic eggs that develop adrift in the oceanrhinocero produces a calf that develops in her womb for 1618 monthsrequire more than a year of care before it becomes fully independentclownfish spend entire adult lives in a single sea anemonemutually beneficial relationship between clownfishanemoneanemone protects clownfish by stinging predatorsclownfish help anemone by eating driving away its predators2 to 6 clownfish live in a single anemonethey are usually not related to one another not family membersinteract based on a strict pecking order based on sizelargest fish is a femalesecond largest is the breeding maleremaining fish are sexually immature nonbreedersif female dies breeding male undergoes growth spurtchanges sex to become a femalelargest nonbreeder increases in sizebecomes new breeding malebreeding male mates with femalecares for fertilized eggs until they hatchjuvenile fish find another anemone to habitenter an anemone if there is room otherwise get rejected by resident fishlife cycle with expulsion hierarchysex changeIntroductionlife history is record of major events related to its growth development reproductionsurvivalex agesize at sexual maturity amounttiming of reproduction survivalmortality ratestimingnature of life history traits are products of adaptation to the environmentLife History DiversityIndividuals within species differ in their historieslife history strategy of species is overall pattern in timingnature of life history events averaged across all individuals in speciesex Homo sapienswomen typically have one baby at a timereproduction usually occurs between ages of 1545life history strategy is shaped by way the organism divides its energy resources between growth reproductionsurvivaldifference between how individuals divide energy are due to genetic variation or difference in environmental conditionsGenetic differencesgenetically influenced traits are those that are more similar in families than between themex siblings are similar in appearancereach similar adult heightsweightsBlue grasslife history traits are similar among sibling plantsex age at first reproduction growth rate number of flowers producednatural selection acts on heritable variation in life history traitslife history is optimaladapted to maximize fitnessfitness genetic contribution of organisms descendents to future generationsno life history results in unlimited production of descendantsconstraints prevent evolution of perfect life historyinvolve ecological tradeoffs in which an increase in performance of one function reduce performance of anotherex reproduction vs growth survivallife history is optimal in the sense of maximizing fitness subject to constraintsEnvironmental differencesphenotypic plasticity is when a single genotype produces different phenotypes under different environmental conditionslife history traits show some degree of plasticityex different growth rate depending on temperaturechanges in life history translate into changes in adult morphologyslower growth in cool condition leads to smaller adult sizedifferent shapeallocate more biomass to leaf growth relative to sapwood production in cool conditionsapwood is newly formed layers of wood that function in water transportallocation is relative amounts of energy resources that organism devotes to different functionsdesert trees are shortersquatter with fewer brancheshave lower photosynthetic rateconsume less carbon dioxide due to fewer leavesphenotypic plasticity that responds to temperature variation produces a continuous range of sizesin some phenotypic plasticity a single genotype produces discrete morphs types with few or no intermediate forms2 morphs of spadefoot toad1 Omnivore morphfeed on detritusalgae2 Carnivore morph
More Less

Related notes for BIOC50H3

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.