bio 4202 evolutionary ecology (vasanth 2019) · plate tectonics - theory that the earth’s crust,...
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BIO 4202
Evolutionary Ecology
(Vasanth 2019)
Ullasa Kodandaramaiah
MODULE: PHYLOGENETICS AND
BIOGEOGRAPHY
Part B: Historical Biogeography
Alfred Wallace (Zoogeographic regions)
Neartic
Neotropical
Ethiopian (Afrotropical) Oriental
(Asian/Indo-Malayan)
Palearctic
Australasian + Oriental + Afrotropical = Old World TropicsPalearctic + Nearctic = HolarcticNearctic + Neotropical = New World
Australasian
SpeciationSpeciation
Allopatric Allopatric - newly formed species occupy different geographic areas
SympatricSympatric – newly formed species occupy the same geographic areas
Historical biogeography –
how did species come to be distributed the way they are?
disjunct distributionsdisjunct distributions
~ place of origin
Parapatric: Speciation with limited geneflow
Peripatric: Small peripheral,isolated population.
founder effect, genetic drift, etc (e.g island colonization)
Species 1 Species 2
Ancestor
Ancestor
Vicariant speciation
Speciation
by dispersal
Historical biogeography perspective -allopatric, peripatric & parapatric: disjunct distributions
ColonizationColonization before before v/sv/s after after
Vicariant speciation between areas A+BC and B+C
A B C
A BC
Speciation by dispersal from area X to Y
XY
Y(sp3)
X YX
(sp2)X
(sp1)
X
BC
A(sp1)
ABC
Ancestral areas
B(sp2)
C(sp3)
Allopatric speciation - disjunct distributions
pre-1960’s era
- belief in a stable earth
- maximum-dispersal model – 'dispersalism', identification of centres-
of-origin
1960’s
- Acceptance of plate tectonic theory (continental drift) - phylogenetics – Willi Hennig
Plate tectonics
Was noted for several centuries that the outlines of some continents appeared as though they could fit together like a jigsaw
best when the outlines are edges continental shelves.
Adapted from Rick Reel's slides
Alfred Wegener – 'Theory of Continental Drift' (accepted in 1960s)
Evidence – shape, fossils, mountain belts, etc
Illustration by Osvaldocangaspadilla, Wikimedia
Soil & rock samples from mountain ranges
Plate Tectonics - theory that the earth’s crust, including the continents and ocean floors, is made up of a series of plates, as plates collide volcanoes occur, and may result in oceanic islands, mountain ranges etc.
Continental Drift - movement over geological time of the earths large land masses as a result of plate tectonics
Image:Rick Cheel
Pangea
Wikimedia
200 MYA – Laurasia begins to separate from Gondwanaland
225 MYA - Pangea
200
Pangea
Breakup of Pangaea/Gondwana
130
India+Madagascar+Seychelles beginning rifting
120
105
Africa breaks off
95
90
88
India-Seychelles separated from Madagascar
Nasikabatrachus sahyadrensis (Pig-nosed frog/Purple frog) Biju and Bossuyt 2003, Nature 425, 711-714
Sooglossidae (Seychelles)Nasikabatrachidae (Western Ghats)
Divergence – ca 130 mya
Photo: Karthick Bala, Wikimedia
85
(New Zealand+New Caledonia) from Australia+Antarctica
Zanis M J et al. PNAS 2002;99:6848-6853©2002 by National Academy of Sciences
50% majority rule tree derived from those trees sampled after “burn in.” (Bayesian Analysis). Posterior probabilities are indicated above the branches (note: not an ultrametric tree).
Image: Wikimedia
Photo: Thomas J. Lemieux
Amborella trichopoda: New Caledonia
Sister to otherflowering plants?
80
70
India from Seychelles ca. 65 mya
60
53
45
Australia starts drifting northwards, split completely by 40
37
SA starts drifting northwards, split completely by 35
30
20
12
10
05
Breakup of Gondwana: summary
India+Madagascar+Seychelles break off 130-80 mya
Africa splits off 105 mya, collision with Eurasia ca 20 mya
New Zealand isolated ca. 85 mya
India separated from Madagascar ca 88 mya (collision with Asia ca 40 mya, Himalayas)
India from Seychelles ca 65
Australia from Antarctica ca.40 mya
SA from Antarctica ca 35 mya (Antarctica circumpolar current & glaciation)
Laurasia
Eastern and Western Palaearctic,Eastern and Western Nearctic
Connected, disconnected and reconnected in different combinations
- Transatlantic bridges - Beringian bridges
South and North America
● isolated since separation of Laurasia from Gondwana
● Reconnected 3 mya
● Isthmus of Panama
Modified from slide by John McCall
50% of extant land mammal genera in South America descend from North American immigrants.
Corresponding figure for North America: 29%
Great American Interchange migrants. Those with a cross by their name became extinct in their new continent.
Modified from slide by John McCall
Great American Interchange
● Fauna exchanged adapted to savannas
● Isthmus >> savanna?
Modified from slide by John McCall
Panamanian Isthmus : Vicariance
Image http://www.shmoop.com/speciation/speciation-geography.html
Altheus (snapping shrimp)Hurt et al 2008 Evolution 63-2: 514–530
Sp 1
Sp 2
Sp 3
Sp 4
Africa
New Zealand
South America
Australia
! simplified
Africa
New Zealand
South America
Australia
taxon-area cladogram
1966 - Lars Brundin - chironomid midges and break-up of Gondwana.
'Phylogeny reflects vicariance' - phylogenetic biogeography
Africa
New Zealand
South America
Australia
India 1
Africa 2South
America 4
New
Zealand 3
Australia 5
Antarctica
PalaeognathaeLiving ratites and tinamous
(large, mainly flightless birds)
7 68
25
1
1. Tinamous: SAm2. Kiwis: NZ3. (Moas: NZ)4. (Elephant birds: Africa)5. Cassowaries: Aus-NG6. Emus: Aus7. Ostrich: Afr-EurA8. Rheas: SAm
(extinct groups)
Slide by Ian Hutchinson
Taxon: 1 2 3 4 5 6 7 8Area: S.Am NZ NZ Ma Au,NG Au Af S.Am
Slide by Ian Hutchinson
Gondwanan vicariancesee also Cooper et al 2001. Nature 409 (6821): 704–70
1
7
4
2,35,68
Gondwana
Illustration by Ian HutchinsonFig: Pearson Prentice Hall Inc
Dispersal
31 spp.
pansies,
buckeyes.
Biogeography of the genus Junonia
(Nymphalidae: Nymphalinae):
Testing hypotheses of vicariance and dispersal
Kodandaramaiah & Wahlberg 2007 Journal of Evolutionary Biology 20: 2181-2191
Extant distribution
17 (15)
10 (8)
3
4 (4)
17 (15) 10 (8)
8 (1)
4 (4)
simple VICARIANCE scenario
simple DISPERSAL Scenario
Phylogeny: predictions
● simple VICARIANCE scenario:
species within different regions form monophyletic
groups.
● simple DISPERSAL scenario:
Asian spp. nested within African
Australian spp nested within Asian
New World spp nested within African
3 genes
1 mitochondrial - COI 2 nuclear - EF1-alpha & wingless
> 3000 bp : 22 spp.
Molecular phylogeny
Kodandaramaiah & Wahlberg 2007. Journal of Evolutionary Biology 20(6) 2181-2191DOI: 10.1111/j.1420-9101.2007.01425.x
Strict Consensus of 791 equally MPT
Bayesian tree
Africa
Oriental (Asia) Asia + Australia
AustraliaAfrica
Africa + Asia + Aust.
New World
Oriental (Asia)
Outgroups (Africa)
Junonia
Predictions:
● simple VICARIANCE scenario:
Species within different regions form monophyletic
groups.
● simple DISPERSAL scenario ?
?
The beginning of things
Outgroups
New World
Molecular Dating estimate (minimum)
20 myCollision of Africa+Arabia with Eurasia
Madagascar
● ca. 80% endemic (95% of the reptiles, 99% of amphibians, and 100% of land mammals excluding bats).
● Radiations: Lemurs, tenrecs, chameleons, dung beetles, etc
Photo: Reuters / www.dailymail.co.uk
Lemur catta (Ring-tailed lemur) Calumma parsonii(Parson's Chameleon)
Photo: Wikimedia / Frank Wassen
Testing vicariance versus dispersal
● Gondwanan vicariance:
- older divergence times
- sister clades in Asia or other Gondwanan fragments
● Post-Gondwanan dispersal
- recent divergence times
- sister clades in Africa
Sister groups of Malagasy clades
Most divergences in the Cenozoic (65 mya to present)
Timing of tenrec speciation events and Madagascar colonization. Divergence times by a Bayesian relaxed molecular clock method, with six time constraints from fossil calibrations. One of them, the paenungulate radiation is represented on the chronogram. Black circles indicate the divergence from the non-Malagasy sister group (node 2) and the initial divergence of Malagasy tenrecs (node 3). Standard deviations are indicated by grey bars, and 95% credibility intervals by open bars. The period of a putative land bridge between Madagascar and Africa at 45–26 Mya [53] is shaded. Poux et al. BMC Evolutionary Biology 2008 8:102 doi:10.1186/1471-2148-8-102
Radiation of tenrecs
Photo: Wikimedia/Wilfried Berns
Echinops telfairi(Lesser Hedgehog-tenrec)
Historical biogeography of India
1) Gondwanan (Out-of-India hypothesis)● e.g. Nasikabatrachus sahyadrensis
reviewed in Datta-Roy & Karanth 2009 J of Biosciences 34 (5) 687-697
2) SE Asia: e.g. Skinks (Datta-Roy et al 2012 Mol Phylogenet Evol 63(3):817–824)
Majority of life forms have affinities to SE Asia (Cenozoic dispersal)
3) Africa: e.g. Junonia
4) Eurasia/Holarctic: E.g Argynnis hyperbius
Photo: Wikimedia/Alpsdake
Argynnis hyperbius(Indian Fritillary)
1) African: Gondwanan, Dispersal from Holarctic, Oriental
2) Australasian: Gondwanan, Dispersal from SE Asia
3) New Zealand: predominantly Dispersal from Oriental/Australia (see Waters & Craw 2006 Syst Biol 2006, 55 (2): 351-356)
4) Neotropical: Gondwanan, dispersal from NA (Great American Interchange)
5) Holarctic: Gondwanan, dispersal from Oriental, African (see Sanmartín et al 2001. BJLS 73: 345-390)
pre 1960’s: dominant view
1960’s: ’the science of the improbable, the rare, the
mysterious and the miraculous’
Now??: dispersal is fundamental to allopatric
speciation
Speciation by 'Dispersal'
Geodispersal
● Dispersal when a barrier is lost
e.g Great American Interchange
Dispersal between Africa & Asia across the Arabian Peninsula