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Biogeography. Lecture 5

Alexey Shipunov

Minot State University

January 29, 2014

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 1 / 34 Outline

Palaeogeography Plate tectonics

Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Ediacarian period: 635–550 Mya period , and : three ages of fishes

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 2 / 34 Outline

Palaeogeography Plate tectonics

Most important eras and periods Cryogenian period (850–635 Mya) and Ediacarian period: 635–550 Mya Cambrian period Ordovician, Silurian and Devonian: three ages of fishes

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 2 / 34 Palaeogeography Plate tectonics

Palaeogeography Plate tectonics

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 3 / 34 Palaeogeography Plate tectonics Mantle convection

I The driving force of floating continents is a mantle convection

I In ocean ridges, new ocean cortex is constantly forming and expanding

I In ocean trenches and continental ridges, different plates are colliding and often forming mountains

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 4 / 34 Palaeogeography Plate tectonics Mantle convection

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 5 / 34 Palaeogeography Plate tectonics Mantle convection

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 6 / 34 Palaeogeography Plate tectonics The result of mantle convection

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 7 / 34 Palaeogeography Plate tectonics What is going on now

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 8 / 34 Palaeogeography Plate tectonics Two living examples of continental drift on U.S. territory

I Yellowstone hotspot

I Hawaiian hotspot

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 9 / 34 Palaeogeography Plate tectonics Yellowstone hotspot

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 10 / 34 Palaeogeography Plate tectonics Hawaiian hotspot

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 11 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth

Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 12 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth —the first super-continent

I Tectonic plates formed (and will form) one continent several times

I 650 Mya this continent—Rodinia was formed right over the South Pole

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 13 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth Cryogenian continents which formed Rodinia

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 14 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth Rodinia: view from South Pole

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 15 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth Marionan glaciation: Snowball Earth

I First global glaciation was started because ice started to concentrate over the pole and increase Earth albedo (this is the positive feedback)

I And because the configuration of continents blocked the equatorial warm current

I And because concentration of oxygen was high but greenhouse gases (like CO2)—small I As a result, from time to time Earth was completely covered with ice sheet 1 km tall!

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 16 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth Star Wars Hoth—ice planet

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 17 / 34 Most important eras and periods Cryogenian period (850–635 Mya) and Snowball Earth Snowball Earth

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 18 / 34 Most important eras and periods Ediacarian period: 635–550 Mya

Most important eras and periods Ediacarian period: 635–550 Mya

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 19 / 34 Most important eras and periods Ediacarian period: 635–550 Mya Rodinia breaks

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 20 / 34 Most important eras and periods Ediacarian period: 635–550 Mya Ediacarian continents

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 21 / 34 Most important eras and periods Ediacarian period: 635–550 Mya in Cryogenian and Ediacarian

I Before: prokaryotes, included photosynthetic (cyanobacteria), then unicellular

I Cryogenian: multicellular eukaryotes, e.g. algae

I Ediacarian: first

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 22 / 34 Most important eras and periods Ediacarian period: 635–550 Mya Ediacarian life

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 23 / 34 Most important eras and periods Cambrian period

Most important eras and periods Cambrian period

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 24 / 34 Most important eras and periods Cambrian period Cambrian map

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 25 / 34 Most important eras and periods Cambrian period Cambrian climate and life

I Gradually changed from colder to warmer

I : appearance of most of phyla with skeleton

I Little or no terrestrial life

I The main driver of animal during Cryogenian–Cambrian was probably oxygenation of water

I One theory states that pre-Cambrian ocean water was muddy and rich of organic compounds, animal filtration changed this condition

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 26 / 34 Most important eras and periods Cambrian period Cambrian life

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 27 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes

Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 28 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes Ordovician period

I Climate changed from hot to glaciated (Gondwana hits the South Pole)

I Marine fauna spread out, especially cephalopods, conodonts and graptolites

I In the end, the first great extinction: 85% of marine species extinct

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 29 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes Silurian period

I Fluctuating climate

I Prospering of marine fauna again

I Land colonization started from plants and !

I South Pole still in the Gondwana

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 30 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes Silurian sea

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 31 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes Devonian period

I Moderate climate becoming warmer

I Exceptionally high sea level

I Greatest diversity of marine fauna in (especially fishes)

I Terrestrial vertebrates: appeared!

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 32 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes Summary

I Continents of Earth are constantly changing their position due to the mantle convection (“plate tectonics”)

I From Cryogenian to Ordovician, super-continent Rodinia broke and climate on Earth became milder

I Most of water-inhabiting animal groups appeared by Ordovician

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 33 / 34 Most important eras and periods Ordovician, Silurian and Devonian: three ages of fishes For Further Reading

A. Shipunov. Biogeography [Electronic resource]. 2014—onwards. Mode of access: http://ashipunov.info/shipunov/school/biol_330 Plate tectonics. http://en.wikipedia.org/wiki/Plate_tectonics

Shipunov (MSU) Biogeography. Lecture 5 January 29, 2014 34 / 34