Island evolutionEvolutionary forces on islandsEvolutionary forces on islandsEvolutionary trends on islands

MorphologyGigantism and nanismGigantism and nanismLoss of dispersal abilities

Pringleophaga marioni, Marion Island

Paractora dreuxi, Marion Island

Lepidoptera: Tineidae

Diptera: Helcomyzidae

Galapaganus, Galapagos Islands Sequiera et al. 2000

Naupactus xanthographus

Naupactus verecundus

Naupactus dissimulator

Galapaganus howdenae

Galapaganus galapagoensis

Galapaganus caroli

Galapaganus vandykei

Galapaganus collaris

Galapaganus conwayensis

Galapaganus ashlocki

mainland/island

winged/apterous

7.2 Mya Sequiera et al. 2000

60

40

20

0

0 20 40 60 80

Arc

Sin

e-t

ransf

orm

ed %

flig

htl

ess

(main

land a

reas)

ArcSine-transformed % flightless(oceanic islands)

80

Roff 1990

Coleoptera

Orthoptera

Diptera

Hemiptera

Psocoptera

Thysanoptera

Neuroptera

Sphenisciformes 18/18 1

Struthioniformes 15/15 1

Gruiformes 17/122 17

nr of speciesflightless/total

nr oftransitions

Porzana monasa (+1828), Kosrae IslandPorzana sandwichiensis (+?1884), Hawaii Islands

Porzana palmeri (+1920, 1948), Laysan IslandPorzana atra, Henderson Island

Amauornis akoofAmauornis favirostrisPorzana monasaPorzana tabuensisPorzana atra

Porzana sandwichensisAmauornis bicolorAmauornis olivieriPorzana palmeriPorzana pusillaPorzana parvaPorzana fuscaPorzana paykulliiPorzana carolinaPorzana flumineaPorzana porzana Anurolimnas fasciatusPoliolimnas flaviventer

Slikas et al. 2002

125 000 y

Kagu, Rhynochetos jubatus, New Caledonia

Rodriguez solitaire, Pezophaps solitaria, RodriguezDodo, Raphus cucullatus, Mauritius

Kakapo, Strigops habroptilus, New Zealand

Anas chlorotis, New Zealand

Anas aucklandia, Auckland Islands

Anas nesiotis, Campbell Islands

Flightless cormorant, Phalacrocorax harrisi, GalapagosCormorant, Phalacrocorax carbo

mandibles

1cm

Apteribis, Hawaii Islands (+)

Oahu Molokai

Lanai Maui

Hawaii

Kauai

Anas wyviliana

Thambetochen xanion

Chelychelynechen quassus

Ptaiochen pau

Thambetochen chauliodous

Sorensen et al. 1999 moa-nalo (+), Hawaiian Islands

Ostriches Struthionidae 1 1 1 AfricaRheas Rheidae 2 2 South AmericaCassowaries Casuariidae 4 4 Australia, New GuineaKiwis Apterygidae 3 3 New ZealandEmus Dromaiidae 1 1 AustraliaMoas Dinornithidae 13 13 New Zealand

Dromornithidae 8 8 AustraliaElephant birds Aepyornithidae 9 9 Madagascar

Dodos Raphidae 2 2 2 Mascarene Islands

Rails Rallidae 17 17 122 Various islandsKagus Rhynochetidae 1 1 1 New Caledonia

Parrots Psittacidae 1 1 358 New Zealand

Ibises Plataleidae 3? ? ? Hawaii

Penguins Spheniscidae 18 1 18 Southern hemisphere

Cormorants Phalacrocoracidae 1 1 37 Galapagos Islands

Grebes Podicipedidae 3 3 21 South America

Murres Alcidae 1 1 23 Atlantic Ocean

Ducks Anatidae 4 2 148 Various coastlines

number of flightless speciesnumber of evolutionary transitions

total number of species

Loss of dispersal abilities

"There is a very curious point in the astounding proportion of Coleoptera that are apterous; & I think I have grasped the reason, viz that powers offlight wd be injurious to insects inhabiting a confined locality & expose them to be blown to the sea"

Darwin, 1855

ecological release(lack of predators)

random driftnot countered

by selection

natural selectionfor energy re-allocation

1.0

0

0 1 2 3

Log

win

gle

ng

th (

cm)

Log body mass (g)

2.0

4

No flightless species

Contains flightless species

Phasantidae

Gavidae

Bird families

McCall et al. 1998

Broom stick, Bidens pilosa, Tropics Bog Beggarticks, Bidens conjuncta, Hawaii Islands

pappus

achene

Lactuca muralis, Vancouver Island Cody & Overton 1996

2000

1-4 5-7 10+Volu

me p

ap

pu

s /

Volu

me a

chen

es

Age (years)

8-9mainland

1500

1000

500

0

Lactuca muralis, Vancouver Island Cody & Overton 1996

Island evolutionEvolutionary forces on islandsEvolutionary forces on islandsEvolutionary trends on islands

MorphologyGigantism and nanismGigantism and nanismLoss of dispersal abilitiesLoss of dispersal abilitiesDevelopment of woodiness

Cabbage tree, Dendroseris litoralis, Juan Fernandez Islands

Sow Thistle, Sonchus fruticosus, Madeira

Narrowleaf plantain, Plantago lanceolata, Eurasia Plantago princeps, Hawaii

Development of woodiness

Competition hypothesisgrowing taller is advantageous

Longevity hypothesiswoodiness allows extended lifespans,

increases chance of sexual reproductionClimate hypothesis

islands have milder andmoister climates

Island evolutionEvolutionary forces on islandsEvolutionary forces on islandsEvolutionary trends on islands

MorphologyGigantism and nanismGigantism and nanismLoss of dispersal abilitiesLoss of dispersal abilitiesDevelopment of woodinessDevelopment of woodinessTendency towards melanism

tendency towards melanism

thermal advantage

lower predation pressure

Viper, Vipera berus, Swedish islands in the Baltic Sea

50

Mela

nis

m f

req

uen

cy (

%)

inland

40

30

10

0

60

70

20

coastal insular

Viper, Vipera berus, Swedish islands in the Baltic Sea Forsman 1995

An

nu

al su

rviv

al ra

te

0.7

0.9

0.5

1986-8787-8888-8989-9090-91

Year

melanistic males

zigzag males

Viper, Vipera berus, Swedish islands in the Baltic Sea Forsman 1995

Japanese four-lined ratsnake, Elaphe quadrivirgata, Yakushima Island Tanaka 2007

devia

tion

fro

mp

refe

rred

ran

ge (

°C)

8

12

0

Jul Sep Oct Nov

Month

melanisticstriped

4

16

Japanese four-lined ratsnake, Elaphe quadrivirgata, Yakushima Island Tanaka 2007