Download Galapaganus

Island evolution
Evolutionary forces on islands
Evolutionary trends on islands
Morphology
Gigantism and nanism
Loss of dispersal abilities
Pringleophaga marioni, Marion Island
Lepidoptera: Tineidae
Paractora dreuxi, Marion Island
Diptera: Helcomyzidae
Galapaganus, Galapagos Islands
Sequiera et al. 2000
winged/apterous
mainland/island
Naupactus xanthographus
Naupactus verecundus
Naupactus dissimulator
Galapaganus howdenae
Galapaganus galapagoensis
Galapaganus caroli
Galapaganus vandykei
Galapaganus collaris
Galapaganus conwayensis
Galapaganus ashlocki
7.2 Mya
Sequiera et al. 2000
Orthoptera
Diptera
Hemiptera
ArcSine-transformed % flightless
(mainland areas)
Coleoptera
80
60
40
20
0
Thysanoptera
0
Psocoptera
20
40
60
80
ArcSine-transformed % flightless
(oceanic islands)
Roff 1990
Neuroptera
nr of species
flightless/total
nr of
transitions
Sphenisciformes
18/18
1
Struthioniformes
15/15
1
Gruiformes
17/122
17
Porzana sandwichiensis (+?1884), Hawaii Islands
Porzana atra, Henderson Island
Porzana monasa (+1828), Kosrae Island
Porzana palmeri (+1920, 1948), Laysan Island
Amauornis akoof
Amauornis favirostris
Porzana monasa
Porzana tabuensis
Porzana atra
Porzana sandwichensis
Amauornis bicolor
Amauornis olivieri
Porzana palmeri
125 000 y
Porzana pusilla
Porzana parva
Porzana fusca
Porzana paykullii
Porzana carolina
Porzana fluminea
Porzana porzana
Anurolimnas fasciatus
Poliolimnas flaviventer
Slikas et al. 2002
Kagu, Rhynochetos jubatus, New Caledonia
Rodriguez solitaire, Pezophaps solitaria, Rodriguez
Dodo, Raphus cucullatus, Mauritius
Kakapo, Strigops habroptilus, New Zealand
Anas chlorotis, New Zealand
Anas nesiotis, Campbell Islands
Anas aucklandia, Auckland Islands
Cormorant, Phalacrocorax carbo
Flightless cormorant, Phalacrocorax harrisi, Galapagos
1cm
mandibles
Apteribis, Hawaii Islands (+)
Chelychelynechen quassus
Thambetochen xanion
Ptaiochen pau
Kauai
Oahu
Molokai
Lanai
Maui
Hawaii
Anas wyviliana
Thambetochen chauliodous
moa-nalo (+), Hawaiian Islands
Sorensen et al. 1999
number of evolutionary transitions
number of flightless species
Ostriches
Rheas
Cassowaries
Kiwis
Emus
Moas
total number of species
1
2
4
3
1
13
8
9
1
Elephant birds
Struthionidae
Rheidae
Casuariidae
Apterygidae
Dromaiidae
Dinornithidae
Dromornithidae
Aepyornithidae
1
2
4
3
1
13
8
9
Africa
South America
Australia, New Guinea
New Zealand
Australia
New Zealand
Australia
Madagascar
Dodos
Raphidae
2
2
2
Mascarene Islands
Rails
Kagus
Rallidae
Rhynochetidae
17
1
17
1
122
1
Various islands
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
"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 of
flight wd be injurious to insects inhabiting a confined
locality & expose them to be blown to the sea"
Darwin, 1855
Loss of dispersal abilities
natural selection
for energy re-allocation
random drift
not countered
by selection
ecological release
(lack of predators)
Log winglength (cm)
2.0
Gavidae
Phasantidae
1.0
Bird families
No flightless species
Contains flightless species
0
0
1
2
3
Log body mass (g)
4
McCall et al. 1998
Broom stick, Bidens pilosa, Tropics
Bog Beggarticks, Bidens conjuncta, Hawaii Islands
pappus
achene
Lactuca muralis, Vancouver Island
Cody & Overton 1996
Volume pappus / Volume achenes
2000
1500
1000
500
0
mainland
1-4
5-7
8-9
10+
Age (years)
Lactuca muralis, Vancouver Island
Cody & Overton 1996
Island evolution
Evolutionary forces on islands
Evolutionary trends on islands
Morphology
Gigantism and nanism
Loss of dispersal abilities
Development of woodiness
Cabbage tree, Dendroseris litoralis, Juan Fernandez Islands
Sow Thistle, Sonchus fruticosus, Madeira
Narrowleaf plantain, Plantago lanceolata, Eurasia
Plantago princeps, Hawaii
Competition hypothesis
growing taller is advantageous
Longevity hypothesis
woodiness allows extended lifespans,
increases chance of sexual reproduction
Climate hypothesis
islands have milder and
moister climates
Development of woodiness
Island evolution
Evolutionary forces on islands
Evolutionary trends on islands
Morphology
Gigantism and nanism
Loss of dispersal abilities
Development of woodiness
Tendency towards melanism
lower predation pressure
tendency towards melanism
thermal advantage
Viper, Vipera berus, Swedish islands in the Baltic Sea
Melanism frequency (%)
70
60
50
40
30
20
10
0
inland
coastal
Viper, Vipera berus, Swedish islands in the Baltic Sea
insular
Forsman 1995
Annual survival rate
0.9
0.7
zigzag males
0.5
melanistic males
1986-87 87-88 88-89 89-90 90-91
Year
Viper, Vipera berus, Swedish islands in the Baltic Sea
Forsman 1995
Japanese four-lined ratsnake, Elaphe quadrivirgata, Yakushima Island
Tanaka 2007
deviation from
preferred range (°C)
16
12
melanistic
striped
8
4
0
Jul
Sep
Oct
Nov
Month
Japanese four-lined ratsnake, Elaphe quadrivirgata, Yakushima Island
Tanaka 2007