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Huntar3cle:CopesruleandBergmannsrulearesomeofthemainmacroevolu3onary
trendsthatinfluencebodysize,animportanttraitthatinfluencesmanyaspectsonthe
biologyofanindividual.Havingrecognizedatrendwithtemperaturechangesandthese
trends,HuntandRoywishedtodeterminesomeofthecauses(mainlyclimatechange)
onthesemacroevolu3onarytrends.UsingdatafrombodysizesofPoseidonamicus(ostracodes)andrecordsofpaleotemperatures,theywouldtestto
seeiftherewerenega3vecorrela3onsintemporalchangesinbodysizeand
temperature,increasesinbodysizethatwereaributabletoevolu3onarychanges
withinalineage,andthattheslopeofatemperature-sizerela3onshipwasconsistent
withmodernpopula3onsingeographicallyseparateloca3ons.Allofthesewere
observedandledtotheoverallconclusionthatifspecieslikePosidononamicusalsoget
thesameresultsthenclimatechangewillhavesignificantimpactsonthebodysizeof
certainindividuals,whichinturnhasasevereeffectontheorganismsbiology.
Lavouear3cle:Thisar3clewouldliketolookintothereasoningofwhytheAfrican
freshwaterbuerflyfishhasremainedinamorphologicalstasisfortensofmillionsofyearsdespitehavingagreatgene3cdivergence.Theyintendedtolookintopossible
explana3onsbycomparinggene3candphenotypicdifferen3a3onamongmany
popula3onsofthisspecies.Mitochondrialgenomesweresequencedtoiden3fy
charactersandtaxon,phylogene3ctreesanddivergence3meswereestablishedthrough
apar33onedBayesianmethod,andphenotypicsimilarityamongsixtaxonpairsbasedon
morphometricmeasurementsinordertoes3matemorphologicaldivergences.Having
es3mateddivergencetohaveoccurredover50myaproposedexplana3onsforthis
phenomenahaveincludedstabilizingselec3on,ecologicalnicheconserva3on,and
gene3canddevelopmentalconstraints.Thisstudycanbeusedasacomplementtothose
thatshowphenotypicvariabilityinagene3callyconstrainedspecies.
Bloisar3cle:Thisismoreofaliteraturereviewthatlooksintounderstandinghowclimate
changethroughouttheCenozoicerahasaffectedindividualmammalianspeciesand
mammaliancommuni3es.Theresponsesofindividualspeciestoclimatechangeincluded
abundancechangeinpopula3ons,gene3cchange,morphologicalchange,andrange
shis,allofwhichrepresenttheimmediatesignsofclimatechangeontheenvironment.
Thecommunityresponseswerefaunalexchangeviaimmigra3on,theincreased
probabilityofspecia3onandex3nc3on,andmul3plelegionsresul3nginfunc3onal
turnover.Itisimportanttounderstandtherela3onshipsamongtheseresponsesand
howtheycanpoten3allyoccursimultaneouslyorresultinacascadeeffect.Thisshould
thenhelpinlayingoutaframeworkforthefullpoten3alofdynamicsformammalian
ecosystemsinresponsetotheaggrega3ngeffectsofclimatechange.
