Tectonics and genetics in topographic evolution

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s and genetics in topographic evolution Hochstetter Lecture 2017 Ferdinand von Hochstetter (1829-1884) German-Austrian pioneer geologist

Wallis, Zoology Dept, OU Dr Phaedra Upton, GNS Science, Lower Hutt Dr Chris Burridge, Zoology Dept, Univ of Tasmania Richard Norris (1945-2016)

topography: 20 million years of geomorphic evolution Little on-land evidence of this long history Geological record: How do we determine the

Marlborough Sediments (sparse, large time gaps) Alpine Fault Fission tracks etc (regional rock uplift, not topography) OSL, 10 Be dating (local

River capture and fish genetics, and molecular clock (a) Middle tectonic example: /Southland (b) Late examples: Marlborough Using geology and

Significance of inherited crustal structure 4. Drainage evolution in Southern Alps during on-going convergence 1.

Live entire life in rivers Common NZ freshwater species: Flathead galaxiids G. vulgaris G. depressiceps G. teviot G. G. paucispondylus Roundhead galaxiids G.

1 s and genetics in topographic evolution Hochstetter Lecture 2017 Ferdinand von Hochstetter ( ) German-Austrian pioneer geologist Auckland, Nelson Dave Craw Geology Department, University of Dunedin, New Zealand in collaboration with: Profs Jon Waters, Graham Wallis, Zoology Dept, OU Dr Phaedra Upton, GNS Science, Lower Hutt Dr Chris Burridge, Zoology Dept, Univ of Tasmania Richard Norris ( ) Mentor, colleague, friend for 40 years Hochstetter arms (from Gregor Macaulay) Acknowledgements in memoriam Dun Mountain, NZ Dunite South Island topography: 20 million years of geomorphic evolution Little on-land evidence of this long history Geological record: How do we determine the history of ranges and valleys when most of the record is continually removed by erosion? Marlborough Sediments (sparse, large time gaps) Alpine Fault Fission tracks etc (regional rock uplift, not topography) OSL, 10 Be dating (local points, not whole catchments) Pliocene sediments Structure of talk Background to fish biological memory 1. River capture and fish genetics, and molecular clock (a) Middle tectonic example: /Southland (b) Late examples: Marlborough Using geology and fish genetics to infer topographic evolution 2. Rise of Southern Alps and development of eastern drainages 3. Significance of inherited crustal structure 4. Drainage evolution in Southern Alps during on-going convergence 1. Galaxiid fish & biological memory in rivers Many species have marine stage Rivers of whitebait fish and gold Some species are freshwater-limited Live entire life in rivers Common NZ freshwater species: Flathead galaxiids G. vulgaris G. depressiceps G. teviot G. G. paucispondylus Roundhead galaxiids G. anomalus G. gollumoides Larger scale synthesis of geomorphic inferences 5. Comparisons of fish to other biota in mountains: onset of glaciation 6. Regional topographic evolution in South Island 7. Speculations on other mountain belts Craw, Min. Dep Pencil galaxiids G. cobitinis G. prognathus G. macronasus 1

Seagoing ancestor Becomes freshwater limited e.g., Fish DNA memory GENETIC EVOLUTION (relative)

Genetic change since islands were connected (mtdna, ndna) 1(a) River capture at /Southland

fish remain in rivers (genetically) for millions of years Nokomai River Large alluvial gold

gollumoides in drainages River capture at Southland boundary Alluvial Au mine Uplift of ranges ~0.

Fe-Mn-Ca garnet from high grade schist Magnetite from high grade schist Gold G.

gollumoides in Southland drainages Cinnabar (HgS) Au Nokomai R Waters et al.

Blenheim Rounded cobbles in terrace: derived Pelorus R.

2 Seagoing ancestor Becomes freshwater limited e.g., Fish DNA memory GENETIC EVOLUTION (relative) TIME (relative) North Island Marlborough, South Island PRESENT Retain memory of ancestral rivers Genetic change since islands were connected (mtdna, ndna) 1(a) River capture at /Southland Queenstown boundary L Wakatipu Wanaka Southland Sediments are constantly eroded & removed but fish remain in rivers (genetically) for millions of years Nokomai River Large alluvial gold deposits Southland gold mines contain some exotic minerals in sand NORTH Nevis R No G. gollumoides in drainages River capture at Southland boundary Alluvial Au mine Uplift of ranges ~0.4 mm/year; Estimate reversal ka Au gollumoides Basement: Low grade schist & greywacke Fe-Mn-Ca garnet from high grade schist Magnetite from high grade schist Gold G. gollumoides ancestor Relict G. gollumoides in captured river 2.7% mtdna divergence Common G. gollumoides in Southland drainages Cinnabar (HgS) Au Nokomai R Waters et al. Evolution 2001 Nelson 1(b) River capture in Marlborough Geology at drainage divide NZJGG 2007 Blenheim Rounded cobbles in terrace: derived Pelorus R. from north Terrace top Locally derived, ka 69±12 ka Luminescence (OSL) dates Gravel terrace: ka (OIS 6) Kaituna R. River capture between OIS 6 and OIS 4: last interglacial, ka 79±9 ka Low grade schist clasts derived from north 1 cm Wairau R. Craw & Waters J Geol Soc London 2007 OIS 6 terrace underlies divide Derived from north ka Imbrication of schist pebbles S flow 5 direction % 2

Late genetic divergence of G. South Pelorus + Kaituna R Havelock Pelorus Sound Pelorus R Kaituna R Wairau R 1.

2% mtdna divergence over 7 ka West Pre-130 ka Waters et al.

2 Chatham Islands for the last 1 Ma 4 3 2 1 Pelorus 0 Fish genetics as a geomorphological dating tool Waiau-Oreti Kaituna Clarence Rough Ridge Nevis-Nokomai Nelson lakes area (3

Rise of Southern Alps in Pliocene: Separated eastern and western fish populations Different genera from : species arise from separation by Southern Alps uplift 10.

2016 paucispondylus paucispondylus: prefers upland gravel rivers 50 km Drainage perpendicular to plate boundary after Koons (1994) Plate motion: 40 mm/year West: High rainfall

3 Late genetic divergence of G. South Pelorus + Kaituna R Havelock Pelorus Sound Pelorus R Kaituna R Wairau R 1.5% mtdna divergence over ka Rivers were connected in sea level low stand Now isolated by sea level rise ca. 7 ka 0.2% mtdna divergence over 7 ka West Pre-130 ka Waters et al. Biol J Linn Soc 2006 DNA sequence divergence, % Theoretical curve fitted through dated fish separation events 6 Genetic age equation: Dating tool 5 y = -2.2e -9x + 2.5x Chatham Islands for the last 1 Ma Pelorus 0 Fish genetics as a geomorphological dating tool Waiau-Oreti Kaituna Clarence Rough Ridge Nevis-Nokomai Nelson lakes area (3 species) Geology 2008 Time, thousands of years Uses of fish biological memory: 1. Identify capture event 2. Define which rivers 3. Estimate timing 2. Rise of Southern Alps in Pliocene: Separated eastern and western fish populations Different genera from : species arise from separation by Southern Alps uplift 10.8% mtdna divergence 2-5 Ma paucispondylus 50 km Nat. Geosci paucispondylus paucispondylus: prefers upland gravel rivers 50 km Drainage perpendicular to plate boundary after Koons (1994) Plate motion: 40 mm/year West: High rainfall High uplift & erosion Closely spaced short steep rivers Rivers at 90 to divide Typical topography in the high Southern Alps Main Divide Plate motion: 40 mm/year Drainage (sub)parallel East: to orogen Low rainfall Low uplift & erosion Widely spaced long rivers Rivers oblique to divide, flow S Genetic continuity along mountains: --Southland Low relief, Orogen-parallel orogen-parallel drainage until mid- drainage G. paucispondylus Same species down eastern side of mountain belt until disrupted in mid- paucispondylus Separate drainage system to east NZJGG

NW drainage 20 ka - boundary Mt Aspiring Major topographic contrast Results

Greenschist Upper Clutha R 150 ka Alpine Fault Strong crust; Greywacke

Greywacke Weak crust; Schist broad low relief folded zone schist greywacke

Miocene, Pliocene, Folded range Faulted barrier between different

Drainage evolution during on-going convergence West convergence East Two

south-draining rivers (b) Erosional passes along overprinting faults

perpendicular to orogen Old divide Divide fault zone Orogen-parallel

4 NW drainage 20 ka - boundary Mt Aspiring Major topographic contrast Results from inherited structure Major influence on fish Upper Greenschist facies Greenschist Upper Clutha R 150 ka Alpine Fault Strong crust; Greywacke narrow high faulted mountains Much still below sea level Greenschist Greywacke Weak crust; Schist broad low relief folded zone schist greywacke Kakanui-Hawkdun Ranges: formed barrier to freshwater fish migration through Miocene, Pliocene, Folded range Faulted barrier between different deformation & topographic regimes Nat. Geosci Drainage evolution during on-going convergence West convergence East Two different types of pass through Main Divide: (a) Old river beds of captured south-draining rivers (b) Erosional passes along overprinting faults Rainfall saw >10 m/year Captured rivers convergence Enhanced drainage perpendicular to orogen Old divide Divide fault zone Orogen-parallel drainage Eastern topography is pushed west passively at >5 mm/year into high rainfall, high erosion zone, resulting in river capture J Biogeog

4a. Lewis Pass: old river bed abandoned when river captured Maruia R Present Maruia R with G.

flows to southwest Present Fault erosion cutting into new Main Divide Maruia R Lewis Pass Old

Divergence of mtdna: 2.9% vulgaris 2.7% Gobiomorphus breviceps 2.

divide along Wairau Fault to WEST Wairau R 50 km to EAST Buller R 240-300 ka ice limit

Comparison of fish to terrestrial biota in Southern Alps Initial growth of Southern Alps: long,

5 4a. Lewis Pass: old river bed abandoned when river captured Maruia R Present Maruia R with G. prognathus Upper Maruia River bends 90 where captured by northeast striking fault zone, and now flows to southwest Present Fault erosion cutting into new Main Divide Maruia R Lewis Pass Old convergence Lewis Pass: old river bed Old prognathus in Maruia R, captured from upper Lewis R Lewis R Capture occurred ka 4b. Low erosional divide along Wairau Fault Fish redistribution at northern end of mountains: Divergence of mtdna: 2.9% vulgaris 2.7% Gobiomorphus breviceps 2.5% Last reproductive contact: 300 ka glacial advance/retreat Motueka R to NORTH (b) Erosional divide along Wairau Fault to WEST Wairau R 50 km to EAST Buller R ka ice limit Gobiomorphus breviceps vulgaris Geology Comparison of fish to terrestrial biota in Southern Alps Initial growth of Southern Alps: long, thin, with narrow central neck Narrow neck was formed in Pliocene combination: inherited crustal structure + new plate boundary Narrow tectonically formed neck in mountain chain paucispondylus Fish separation by long narrow drainage divide Inherited crustal structure Geology

Alpine terrestrial biota: Transverse division

Longitudinal division along mountain divide

risen in Uplifted remnants of Pliocene fluvial

populations of four fish species Fish dating +

Uplifted and deformed remnants of fluvial

coastal plains on both sides of neck Upton et

Flathead galaxiids: diversity in eastern South

vulgaris over large areas OTAGO SCHIST Weak

6 Alpine terrestrial biota: Transverse division across mountains Different from fish: Longitudinal division along mountain divide neck Pliocene mountain front foothills have risen in Uplifted remnants of Pliocene fluvial sediments Geology 2017 Local divide separated populations of four fish species Fish dating + uplifted sediments => Late uplift of foothills Uplifted and deformed remnants of fluvial sediments Biological memory of first temperate glaciation? PRESENT Time since separation 3 Ma Ice reached coastal plains on both sides of neck Upton et al. NZJGG 2004; Waters & Craw Fwater Biol 2007; Geology 2017 Geology South Island regional synthesis Transverse Flathead galaxiids: diversity in eastern South Island MARLBOROUGH Strike-slip faults 1 species related to G. vulgaris CANTERBURY Strong crust, faults G. vulgaris over large areas OTAGO SCHIST Weak crust, folds 7 species related to G. vulgaris Nat. Geosci SOUTHLAND Strong crust, faults 2 species related to G. vulgaris Nature Geosci

7(a): South American terrestrial biota as a thermometer for progressive early global cooling?

Himalayan transverse faunal discontinuities Glacial, in deep erosional gorges NORTH Transverse extension: Kali Gandaki R graben

? Genetic discontinuities In terrestrial biota Images: Luke Easterbrook-Clarke from SRTM data Alluvial fan deposits in graben

Northward evolution of depression Long-term transverse depression Biological memory of long-term transverse corridor from Tibet

speciation = middle Miocene (>8 Ma) TIBETAN PLATEAU 18 species Common ancestor in Miocene 5 species Conclusions Separate

populations evolved in varying states of isolation in the separate geomorphic zones Freshwater fish carry information about the

information can provide evidence for previous drainage connections and severance events, and can estimate timing for these Alpine

7 7(a): South American terrestrial biota as a thermometer for progressive early global cooling? Biological memory may retain the only on-land record (A good project for the future?) 7b. Himalayan transverse faunal discontinuities Glacial, in deep erosional gorges NORTH Transverse extension: Kali Gandaki R graben WEST EAST?? Genetic discontinuities In terrestrial biota Images: Luke Easterbrook-Clarke from SRTM data Alluvial fan deposits in graben Geological record cannot distinguish evolutionary histories Extension Extension P Upton photo Miocene-Pliocene Mesozoic Mesozoic Northward evolution of depression Long-term transverse depression Biological memory of long-term transverse corridor from Tibet Flightless beetles: migrated south & speciated to east and west of graben (+ later dispersal & overlap) DNA estimate: migration & speciation = middle Miocene (>8 Ma) TIBETAN PLATEAU 18 species Common ancestor in Miocene 5 species Conclusions Separate tectonic-geomorphic zones evolved in South Island through Miocene-Recent uplift and evolution of landscape Freshwater fish populations evolved in varying states of isolation in the separate geomorphic zones Freshwater fish carry information about the geomorphic evolutionary history in their genes that is difficult to extract from the geological record otherwise This genetic information can provide evidence for previous drainage connections and severance events, and can estimate timing for these Alpine terrestrial biota carry an entirely different genetic memory dominated in NZ by the first glaciation, with a prominent transverse discontinuity Schmidt et al. PLoS Image: Luke Easterbrook-Clarke from SRTM data Genetic data can augment geological tools, with some limitations (like other tools), for unravelling geomorphological history in mountain belts 7

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