BAESI

1. March 5, 2011: FOSSILS: Fossil Kits Instructor: Jonathan Hendricks Assistant Professor of Paleontology, SJSU, Dept. Geology Email: jonathan.hendricks@sjsu.edu BAESI

2. Polished Elimia Agate Specimen 1

3. Phylum: Mollusca Class: Gastropoda (snails) Genus: Elimia Fossil location: Wyoming. Fossil age: Eocene (~50 million years old). Environment: Ancient lakebed. Preservation: original calcium carbonate shell (unaltered). Slide shows a picture of polished Elimia agate. 1. Polished Elimia Agate Activity idea: “round rocks”.

4. Fossiliferous Limestone Specimen 2

5. Phylum: Mollusca. Classes: Gastropoda (snails) and Bivalvia (clams). Fossil location: Texas Fossil age: Probably Cretaceous (~100 million years old). Environment: Shallow marine. Preservation: Molds. Slide shows a picture of fossiliferous limestone. 2. Fossiliferous Limestone Activity idea: “round rocks”.

6. Black Shale Specimen 3

7. 3. Black Shale • Sample does not contain visible fossils. • Sample location: Montana. • Sample age: unknown. • Environment: probably deep marine; dark color indicates high organic content. Slide shows a picture of a piece of black shale.

8. Stromatolite / Banded Iron Specimen 4

9. 4. Stromatolite / Banded Iron • Major division of life: Prokayota (bacteria). • Fossil location: Minnesota. • Fossil age: Proterozoic (~ 2-2.5 billion years old). • Environment: Shallow marine. • Red color due to high iron content (rock type is “Banded Iron Formation”). Slide shows a picture of a sample of banded iron formation.

10. Slide shows pictures of stromatolites. Stromatolites Stromatolites:mat-like structures formed mostly by photosynthesizing cyanobacteria. Slimy layers + sediment. Oxygen by-product of photosynthesis. Fossil Record: Archean (become more abundant and diverse in Proterozoic) to Today Mostly found today where grazing animals like snails cannot eat them. Photo by Rygel (Creative Commons) Photo by Mark A. Wilson (Wikipedia)

11. Stromatolites Today Shark Bay, Australia • Slide shows photographs of some modern examples of stromatolites. Photograph by Paul Harrison (Creative Commons)

12. Banded Iron Formation, 2 Ga Banded Iron Formations (BIF’s) Slide shows a pictures of banded iron formation in the field and modern ‘black smoker” hydrothermal vents. USGS Iron Modern “Black Smokers” Layers of iron-rich (red!) sediments (rust = FeO2). Major world supply of iron ore for steel production. Formed between ~3.5 and 1.9 billion years ago. Could only have formed in nearly oxygen-free (anoxic) seawater. Stromatolitic origin. Iron moved to near shore from far away; (photosynthesizers near shore caused precipitation of FeO2). BIF extinction due to rise in oxygen! (by 2.0 Ga, 15% of today’s levels). Iron NOAA

13. Bivalve Specimen 5

14. 5. Bivalve (Ilymatogyra) • Phylum: Mollusca. • Class: Bivalvia. • Genus: Ilymatogyra. • Fossil location: Texas. • Fossil age: Cretaceous (~95 million years old). • Environment: marine; conditions suitable for filter feeding. • Preservation: original shell. Slide shows a picture of a specimen of Ilymatogyra.

15. Bivalvia = Pelecypoda Clams, oysters, cockles, scallops, and mussels. Cambrian to Recent. 15,000 extant species, 40,000+ fossil species. Two valves (CaCO3). No head, few sense organs. Foot used for burrowing. Gills modified for respiration and filter feeding. Mostly sessile, aquatic filter feeders. Slides shows an illustration (by Ernst Haeckel) of a variety of bivalve shells. Class Bivalvia By Ernst Haeckel.

16. Brachiopod Specimen 6

17. 6. Brachiopod (Atrypa) • Phylum: Brachiopoda. • Genus: Atrypa. • Fossil location: Morocco. • Fossil age: Ordovician or Silurian period (488 to 416 million years ago). • Environment: marine; conditions suitable for filter feeding. • Preservation: some original shell; internal mold. Slide shows a picture of a fossil brachiopod.

18. “Lamp shells” Two calcitic (typically) valves. Marine; sessile, intertidal to abyssal. Filter feeders (using lophophore). Paleozoic: great diversity and abundance. Today: cryptic and 120 genera. Slide shows a photograph of a brachiopod shell. Phylum Brachiopoda

19. Crinoid Stem Specimen 7

20. 7. Crinoid Stem • Phylum: Echinodermata. • Class: Crinoidea. • Fossil location: Texas. • Fossil age: Mississippian Period (~340 million years old). • Environment: marine. • Preservation: original calcite stem. Slide shows a picture of a specimen of crinoid stem.

21. “Sea lilies” Most of diversity extinct (~700 extant species; 6000 extinct species). Ordovician to Recent. “Starfish on a stick”: arms, calyx, stem, root. Filter feeders; tube feet on arms move food to mouth. Stem segments have produced “crinoidallimestones”. Slide shows an illustration of various crinoids by Ernst Haeckel. Class Crinoidea By Ernst Haeckel.

22. Interpreting Crinoid Fossils Slide shows a photograph of crinoid stem pieces and a drawing of fossils made by Gesner. From Wikipedia Commons.

23. Gastropoda Specimen 8

24. 8. Gastropoda (Wortheniatabulata) • Phylum: Mollusca. • Class: Gastropoda (snails). • Fossil location: Missouri. • Fossil age: Pennsylvanian Period (~312 million years old). • Environment: marine. • Preservation: Cast. Slide shows a picture of a specimen of a fossil gastropod (snail).

25. Snails and slugs. Most diverse mollusk group (~100,000 species). Cambrian to Recent. Members occupy many different habitats: marine (benthic and pelagic), freshwater, and terrestrial. Slide shows an illustration of gastropod shells by Ernst Haeckel and a photograph of a modern land snail. Class Gastropoda By Ernst Haeckel. From Wikipedia Commons

26. Ammonite Specimen 9

27. 9. Ammonite • Phylum: Mollusca. • Class: Cephalopoda (subgroup Ammonoidea). • Fossil location: Morocco. • Fossil age: Jurassic Period (~176 million years old). • Environment: marine; animal lived in the water column. • Preservation: original shell; internal mold. Slide shows a picture of an ammonoid specimen.

28. 650 extant species; 17,000 extinct species. Late Cambrian to Recent. Subclasses: Coleoids (squids, octopi, and cuttlefish), nautiloids, endoceratoids, and ammonoids. Slide shows an illustration by Ernst Haeckel of various extant cephalopods and a photograph of a model of a modern nautilus. Class Cephalopoda By Ernst Haeckel.

29. “Serpent Stones” “Horns of Ammon” Slide shows various illustrations of ammonoids drawn by Ernst Haeckel. Ammonoids

30. Horn Coral Specimen 10

31. 10. Horn Coral (Triplophyllites) • Phylum: Cnidaria. • Class: Anthozoa (subgroup Rugosa). • Fossil location: Kentucky. • Fossil age: Mississippian Period (~340 million years old). • Environment: marine. • Preservation: original skeleton. Slide shows a picture of a specimen of horn coral.

32. Skeleton calcitic. Some solitary, some colonial. Middle Ordovician to Permian. Most diverse (800 genera) and abundant Paleozoic corals. Slide shows two photos of horn coral fossils. Order Rugosa (“Horn Corals”)

33. Devonian rugose corals. Show two types of growth layers: thick and thin. Thick: annual/seasonal. Thin: day/night cycles. Wells counted number of thin (daily) bands between thick (annual) bands. Devonian corals: 400. Pennsylvanian: 387. What does this mean? Slide shows a picture of a rugose coral fossil with many growth lines. The Work of John Wells

34. Shark Tooth Specimen 11

35. 11. Shark Tooth • Phylum: Chordata. • Class: Vertebrata (Major Group: Chondrichthyes). • Fossil location: Morocco. • Fossil age: unknown. • Environment: marine. • Preservation: original bone (?). Slide shows a picture of a fossil shark tooth.

36. Dinosaur Bone Specimen12

37. 12. Dinosaur Bone • Phylum: Chordata. • Class: Vertebrata (Major Group: Tetrapoda). • Fossil location: unknown. • Fossil age: Jurassic Period (~176 million years old). • Environment: terrestrial. • Fossil preservation: permineralization. Slide shows a picture of a specimen of dinosaur bone.

38. Petrified Wood Specimen13

39. 13. Petrified Wood • Kingdom: Plantae. • Fossil location: unknown. • Fossil age: unknown. • Environment: terrestrial. • Fossil preservation: permineralization. Slide shows a picture of petrified wood.

40. Trilobite Specimen14

41. 14. Trilobite: Elrathia • Phylum: Arthropoda. • Major Group: Trilobita. • Fossil location: Utah. • Fossil age: Cambrian (~507 million years old). • Environment: marine. • Fossil preservation: unaltered calcitic exoskeleton. Slide shows a picture of an Elrathia trilobite specimen.

42. Parts of a Trilobite • Cephalon (Head) • Thorax (Middle) • Pygidium (Tail) • Activity: Which parts of Elrathia are preserved in your samples? • Slide shows a drawing that details the parts of a trilobite. Drawing by Sam Gon III

43. Cambrian (maximum diversity) to Permian. About 1200 genera. Most important fossils for dating Cambrian rocks. Exoskeleton: mostly calcite; had to molt to grow. Cephalon (=head; facial sutures), thorax, pygidium (=tail). Thoraxes show trilobation. Slide shows an illustration of trilobites by Ernst Haeckel and a photograph of two trilobite fossils. Trilobita By Ernst Haeckel.

44. Trilobite Eyes & Enrollment • Slide shows a photograph of trilobite eyes. Photo by SNP (Creative Commons) Photo by Moussa Direct Ltd. (Creative Commons)