Evolutionary History 0 5 bya Cambrian 0 24

Evolutionary History

0. 5 bya: Cambrian 0. 24 bya: Mesozoic 0. 065 bya: Cenozoic 0. 9 bya: first animals 1. 8 bya: first eukaryote 2. 3 -2. 0 bya: Oxygen 4. 0 bya: Oldest Rocks 3. 4 bya: Oldest Fossils 4. 5 bya: Earth Forms The Phanerozoic Eon

The Phanerozoic Eon

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna The first fossil animals

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna The first fossil animals – A Radiation of Soft-Bodied Forms Spriggina – Annelid or soft-bodied precursor to Arthropods? (Trilobitelike) Dicksonia - thought to be a segmented worm

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna The first fossil animals – A Radiation of Soft-Bodied Forms Tribrachidium - soft-bodied, but enigmatic. . . maybe a cnidarian or an echinoderm. . ? ? ? Kimberella - recent analysis suggest it might be an early mollusc. . a bit chiton-like. . .

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna The first fossil animals – A Radiation of Soft-Bodied Forms The weird ‘rangeomorphs: At ocean bottom (not photosynthetic) Precursors to sponges?

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna The first fossil animals – A Radiation of Soft-Bodied Forms True sponges: The first animals with a “shell” Cloudina Are bore-holes evidence of predation?

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna The first fossil animals – and Cnidarian Predators Cyclomedusa - Cnidarian polyp; up to 1 meter in diameter Eoporpita - Cnidarian polyp

I. The "Precambrian“: The Vendian Period (650 – 543 mya) - The Ediacaran Fauna - Key points: Radiation of the earliest animals: soft-bodied prey and predators representatives of several animal phyla Arkarua: - Echinoderm? Charnia - sea pen (related to Cnidarians) - up to 1 m long

I. The "Precambrian“: The Vendian Period (650 – 543 mya) II. The Paleozoic (543 – 252)

I. The "Precambrian“: The Vendian Period (650 – 543 mya) II. The Paleozoic (543 – 252 mya) A. Cambrian Period (543 -488 mya) - an explosion of fossil animals, representing nearly every modern phyla and several extinct phyla

II. The Paleozoic Era A. The Cambrian Period Burgess Shale Formation

II. The Paleozoic Era A. The Cambrian Period Burgess Shale Community

I. The "Precambrian“: The Vendian Period (650 – 543 mya) II. The Paleozoic (543 – 252 mya) A. Cambrian Period - an explosion of fossil animals, representing nearly every modern phyla and several extinct phyla Thaumaptilon Sea Pen - Cnidaria

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Sydneyia - Arthropod

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Canadia - Annelida

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Choia - Porifera

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Aysheaia - Onychophora

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Ottoia - Priapulida

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Canadapsis - Arthropoda (Crustacea)

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Waptia - Arthropoda (Crustacea)

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Leanchoilia - Arthropoda (Crustacea)

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Pikaia - Chordata

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of extant phyla: Hallucigenia - Onychophora

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of EXTINCT phyla or subphyla: Olenoides – Trilobita (Arthropoda)

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of EXTINCT phyla or subphyla: Marella - primitive Arthropod

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of EXTINCT phyla or subphyla: Haplophrentis - Hyolithid

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of organisms unassigned to any major group: Opabinia

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of organisms unassigned to any major group: Amiskwia

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: examples of organisms unassigned to any major group: Wiwaxia

II. The Paleozoic Era A. The Cambrian Period - an 'explosion' of fossil animals: Anomalocaris

II. The Paleozoic Era A. The Cambrian Period WHY?

II. The Paleozoic Era A. The Cambrian Period - First major radiation of hard-bodied org's Predation? The Vendian radiation contained lots of predators…Cnidarians. Hard parts would be adaptive protection against these predators, as well as the predators in the Cambrian. Sampling Error? Since hard-parts fossilize better than soft parts, is the 'Explosion' just a reflection of the greater likelihood of fossilization? Oxygen levels? O 2 levels increase from 1 -3% to 10% in atmosphere… allowing for more active, mobile animals and also shells covering surfaces. Cambrian Explosion

II. The Paleozoic Era A. The Cambrian Period - First major radiation of hard-bodied org's Our first example of innovation, radiation, and competitive contraction Hard parts

II. The Paleozoic Era A. The Cambrian Period - First major radiation of hard-bodied org's Our first example of innovation, radiation, and competitive contraction

- The Cambrian Fauna and Beyond The fauna was dominated by trilobites. . . and the number of trilobite families peaked in the late Cambrian and declined through the Paleozoic. This marine fauna is known as the 'Cambrian Fauna' and represents the first great marine faunal assemblage in the fossil record.

- The Cambrian Fauna and Beyond This fauna was replaced by the 'Paleozoic' ( or Brachiopod) fauna, and then by the Modern (or 'Gastropod-Mollusc') fauna in the Mesozoic.

II. Paleozoic A. Cambrian - evolution of chordates Pikaia Cephalochordata Euchordata Hagfish (skull but no vertebrae. . . ) Myllokunmingia 530 mya Haikouichthys 530 mya Craniata Vertebrata

- evolution of chordates Myllokunmingia 530 mya Nature 1999

Haikouichthys ercaicunensis early Cambrian perhaps more advanced than Myllokunmingia, but both may have had cartilaginous vertebrae. . . the first true verts! Nature 2003 Myllokunmingia 530 mya

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya)

II. Paleozoic A. Cambrian B. Ordovician - Invertebrate Radiations and Innovations: - Nautiloid Molluscs radiate as predators

During the middle Ordovician some long-shelled forms like Endoceras and Cameroceras attained lengths of 4 to as much as 10 meters - among the largest molluscan shells ever

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) - Invertebrate Radiations and Innovations: - Nautiloid Molluscs radiate as predators - Brachiopods (Lophophorates, not Molluscs) radiate dramatically – adapt to sessile lifestyle

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) - Invertebrate Radiations and Innovations: - Stromatoporoid (sponge) Reefs and Crinoid Reefs evolve

Crinoids are sessile echinoderms, attached to substrate by a stalk.

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) - Invertebrate Radiations and Innovations: - Plants: The first plants evolve on land, represented only by fragments with a distinct cuticle and spores. Probably ‘liverwort’ ancestors dependent on a wet environment. 1 meter long

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) - Invertebrate Radiations and Innovations: - Plants: - Vertebrates: - the first radiation of fishes – the jawless ostracoderms Ordovician Silurian Lampreys** Heterostracans Astraspids Arandaspids "Ostracoderms“ (paraphyletic group) Osteostracans JAWED FISHES

"Ostracoderms" Bony plates; no paired fins; gill arches detrital or predatory feeders Arandaspida Astraspis

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) - The Ordovician Mass Extinction event: 49% of marine genera Strongest Ice Age in Phanerozoic Gondwana over south pole

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya)

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) - Invertebrate Radiations and Innovations: Sea scorpions continue to radiate,

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) - Invertebrate Radiations and Innovations: Sea scorpions continue to radiate, and their sister groups— semi-aquatic scorpions and terrestrial millipedes—evolve Pneumodesmus newmani – the oldest air-breathing, fully terrestrial animal. Has spiracles for respiration.

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) - Invertebrate Radiations and Innovations: - Plants:

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) - Invertebrate Radiations and Innovations: - Plants: Evolution and radiation of the first vascular plants. Four species of Cooksonia, and representatives of the Lycophytes (Baragwanathia)

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) - Invertebrate Radiations and Innovations: - Plants: - Vertebrates: ORDOVICIAN SILURIAN Lampreys** Heterostracans Astraspids Arandaspids "Ostracoderms" Osteostracans JAWED FISHES

- Radiation of Heterostracans - over 300 species

- Radiation of Osteostracans bottom-feeders, but with an important evolutionary advancement - paired fins

- Evolution of Jawed Fishes: - Acanthodians

- Evolution of Jawed Fishes:

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) “The Age of Fishes”

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) - Invertebrates: In the oceans, the Sea Scorpions reach their largest size in Jaekelopterus, nearly 3 m long (the Largest Arthropod ever).

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) - Invertebrates: On land, the earliest fossil insect appears, recognized by the mandible. Rhyniognatha hirsti

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) - Invertebrates: And the first fossil spider Attercop, and a sister group of mites, the Trigonotarbids (no silk)

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) - Invertebrates: - Plants: - Lycopod forests, then dominance by the progymnosperms dominated by one genus, Archaeopteris – 20 m – spores, not seeds

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) - Invertebrates: - Plants: - Vertebrates: - the last ostracoderm Psammolepis over 2 m

II. Paleozoic D. Devonian (416 -360 mya) - Vertebrates: - the last ostracoderm - the major radiation of jawed fish groups Arthrodires Placoderms Antiarchs Chondrichthyes (Sharks, rays) Acanthodians Teleosts Ray-finned Fishes Bony Fish Lobe-finned Fishes

II. Paleozoic D. Devonian (416 -360 mya) - Vertebrates: All in one deposit! Fishes of the Middle Devonian locality of Lethen Bar, in Scotland (Givetian, about 377 Ma). They include antiarchs (1 Pterichthyodes); and arthrodire (2. Coccosteus) placoderms, acanthodians (3. Diplacanthus), ray-finned fish (4, Cheirolepis), lungfish (5, Dipterus), and osteolepiform lobe-finned fish (6. Osteolepis), representing the lineage that gave rise to land animals.

D. Devonian (417 -354 mya) - Placoderms - Sharks - Lobe-finned Fishes - Ray-finned Fishes - Tetrapods (from lobe-finned fishes)

- Placoderms - very abundant - head shields - shearing or crushing tooth plates Dunkleosteus - 6 m Arthrodire Antiarch

- Placoderms - Sharks Stethacanthus - 2 m

- Placoderms - Sharks

- Placoderms - Sharks - Ray-finned Fishes

- Placoderms - Sharks - Ray-finned Fishes - Lobe-finned Fishes Coelacanth

II. Paleozoic D. Devonian (416 -360 mya) - Vertebrates: - the last ostracoderm - the major radiation of jawed fish groups - the evolution of terrestrial vertebrates

D. Devonian (417 -354 mya) - Placoderms - Sharks - Lobe-finned Fishes 365 mya 385 mya

Eusthenopteron

Panderichthys rhombolepis

Tiktaalik roseae

Acanthostega gunnari

Ichthyostega sp.

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) E. Carboniferous (360 -300 mya)

E. Carboniferous (359 -300 mya) - inverts: Arthropleura -largest terrestrial arthropod - 2 m

E. Carboniferous (359 -300 mya) - inverts: - radiation of insects - evolution of flight Meganeura monyi - largest insect ever wingspan of 70 cm

E. Carboniferous (359 -300 mya) - inverts - plants The early Carboniferous saw a reduction in the Devonian forests and a dominance of small plants - lycopods and their kin. Lepidodendron Psaronius - fern Lebachia - progymnosperm Cordaites - progymnosperm

E. Carboniferous (359 -300 mya) - inverts - plants The early Carboniferous saw a reduction in the Devonian forests and a dominance of small plants - lycopods and their kin. As the period proceeds, the giant lycopsid swamp forests evolve across the tropical continent of Euramerica. There was lots of photosynthesis, but this was not balanced by decomposition (because much of the biomass was preserved in sediment, not broken down by decay). So, oxygen production by photosynthesis exceeded oxygen consumption by decomposition. . . and oxygen levels were probably very high. . . this may have allowed the enormous size of invertebrates.

E. Carboniferous (359 -300 mya) - inverts - plants

E. Carboniferous (359 -300 mya) - inverts - plants Coal deposits in shallow tropical swamps

E. Carboniferous (359 -300 mya) - inverts - plants - verts - Sharks replace placoderms as dominant predator in oceans

The golden age of sharks - 45 Families (currently 21)

E. Carboniferous (359 -300 mya) - inverts - plants - verts - Sharks replace placoderms as dominant predator in oceans - Ray-finned fishes dominate in freshwater habitats

- verts radiation of stem tetrapods!!

E. Carboniferous (359 -300 mya) - inverts - plants - verts - Sharks replace placoderms as dominant predator in oceans - Ray-finned fishes dominate in freshwater habitats - Radiation of ‘stem’ tetrapods "crown" tetrapods Seymouriamorpha Temnospondyls Ichthyostegans

E. Carboniferous (359 -300 mya) - inverts - plants - verts - Radiation of ‘stem’ tetrapods Temnospondyls a very diverse radiation of tetrapods, from alligator-like salamanders to large, scaled, frog-like creatures.

Seymouriamorpha Radiate in Permian but earliest fossils from the Carboniferous. . . larvae have external gills, which pulls them out of the amniota. . .

- verts radiation of stem tetrapods!!

The Amniote Divide The amniotic egg was a big advance Resist desiccation - amnion protects the embryo - yolk sac provides nourishment - allantoic sac holds waste produced by embryo Provision embryo allows for colonization of dry habitats

Primitive Amniotes Hylonomus lyelli – an early reptile Carboniferous of Nova Scotia

E. Carboniferous - Verts: - The Amniote Radiations SYNAPSID Anapsid ancestor ANAPSID (turtles? ) Hylonomus Casineria DIAPSID

II. Paleozoic A. Cambrian (544 -488 mya) B. Ordovician (488 -444 mya) C. Silurian (444 -416 mya) D. Devonian (416 -360 mya) E. Carboniferous (360 -300 mya) F. Permian (300 -251 mya)

F. Permian (300 -251 mya) Pangaea forms The fusion of land masses reduced the amount of humid coastline and increased the extent of dry inland areas. This favored the amniote radiations over "amphibian" clades.

F. Permian - The Amniote Radiations Diversify SYNAPSID Anapsid ancestor ANAPSID (turtles) Hylonomus DIAPSID

F. Permian (300 -251 mya) Synapsids dominate through the early Permian Pelycosaurs Dicynodonts Gorgonopsids Therapsids Cynodonts Mammals

F. Permian (300 -251 mya) Pelycosaurs dominate early include the great sail-finned animals like Dimetrodon

F. Permian (300 -251 mya) Early Therapsids, like Gorgonopsids, dominate in the mid-late Permian Moschops Dinocephalians

F. Permian (300 -251 mya) Dicynodonts come to numerical dominance in the late Permian abundant herbivores

F. Permian (300 -251 mya) and the first Cynodonts appear

F. Permian (300 -251 mya) large herbivorous anapsids were also present

F. Permian (300 -251 mya) Diapsids were small and lizard-like; the Synapsids ruled terrestrial communities

F. Permian (300 -251 mya) - Plants!!

F. Permian (300 -251 mya) - the dry climate reduced the great Carboniferous swamp forests; lycopods shrink. . . - Ferns, and gymnosperms ("seed ferns", Ginkos, Cycads, and Conifers) gain prominence. . . - In particular Glossopteris - a seed fern - that produces seeds on its leaves like sori of ferns. . . The evolution of gymnosperms introduced two important adaptive features: - pollen (male gametophyte) - no more swimming sperm; reduced reliance on open water habitats - seed - protective seed coat reduced desiccation of embryo, and nutritious endosperm provisioned the embryo with energy. (Like the amniote egg).

F. Permian (300 -251 mya) The great Permian extinction!!!! A huge mantle plume rises towards the surface. . .

F. Permian (300 -251 mya) The great Permian extinction!!!! A huge mantle plume rises towards the surface. . . resulting in a great bubble of flowing lava. . . the Siberian flats (200, 000 squ. mi)

F. Permian (300 -251 mya)

F. Permian (300 -251 mya) - results: 90 -95% of marine species go extinct. . . 70% of all land species go extinct…

F. Permian (300 -251 mya) - results: 90 -95% of marine species go extinct. . . trilobites placoderms acanthodians 70% of all land families pelycosaurs