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Paleontology 6: Paleozoic Era

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Paleontology 6: Paleozoic Era PALEONTOLOGY 6: PALEOZOIC ERA VOLUME 9, ISSUE 6, FEBRUARY 2020 THIS MONTH WEIRD AND WONDERFUL DIVERSITY OF LIFE • The Land Invasion Dioramas page 2 • DNA The root words of Phanerozoic: changing with new information. ○ Extracting page 7 • phaneros (Greek) visible, New finds will reveal new ○ Mitosis page 8 evident information. Fossils are hard ○ Forensic Sequences • zoion (Greek) animal evidence. Scientists can say page 11 that this did occur. New fossils ○ Phylogenetic In the 1950s, geologists may tell a deeper and richer Sequences page 15 developed the systematic study story. ○ DNA RNA Tutorial & of animal fossils. With the Definitions page 17 Cambrian Explosion (the burst Science is amazing! • Paleozoic Period of fossils from the Early Timeline page 22 Cambrian 541 MYA), scientists thought they had identified the POWER WORDS origins of animals. Later, • dynamic: characterized additional fauna was found in by constant change, the Precambrian. Oops! We activity, or progress still recognize the start of the • eon: a major division of Cambrian Period in the geological time, Paleozoic Era as the beginning subdivided into eras of the Phanerozoic Eon. • MYA: million years ago • Phanerozoic Eon: As you know from making your current eon in geologic own timeline of Earth’s history, time scale, covering the the Hadean, Archean, and past 541 million years Proterozoic Eons are not to • systematic: done to a scale in the image to the right. fixed plan or system The Phanerozoic Eon is scaled. CAREER CONNECTION With this issue, you will begin • Your Personality and the survey of life during the Interests page 31 Paleozoic Era as revealed by the fossil record. Science is dynamic knowledge, constantly COLORADO STATE UNIVERSITY EXTENSION 4-H PROGRAMS ARE AVAILABLE TO ALL WITHOUT DISCRIMINATION THE LAND INVASION — Plants Edge onto Land 2 Cambrian (485-540 MYA): plants and the ice age at the end POWER WORDS At the beginning of the of the Ordovician. Below is an • bryophyte: small, non- Paleozoic Era, weird and image of a carpet of moss. vascular wonderful invertebrate animals • invertebrate: an animal squirmed, wiggled, and swam. lacking a backbone Land, however, was barren. No • terrestrial: of, on, or plant had edged its way to cover relating to land on the bare bedrock. Earth; inhabitant of Earth What do you think the land • tetrapod: means “four looked like before plants? The foot” vertebrate animals image below is a NASA image other than fish of Mars. While Mars may have (amphibians, reptiles, had oceans, lakes, and rivers in birds, and mammals) the past, now the only water is Silurian (419-443 MYA): • vascular: relating to or deep underground or frozen. It The fossil Cooksonia (drawing denoting the plant would have been different on below) is the first known land tissues (xylem and Earth, with our oceans teeming plant with vascular tissue (like phloem) which conduct with life. The image could have ferns). It was just a inch tall with water, sap, and been what Earth looked like an upright stalk. The bryophytes nutrients in flowering before plants invaded the land. were still the dominant plant. plants, conifers, ferns, Apparently the low-lying carpet and their relatives. of plants provided enough protection for the first air- breathing animals on land, the arthropods. The oldest known terrestrial animals found are a scorpion found in rock 350 MYA and a millipede from 428 MYA. Devonian (359-419 MYA): First forests (image below) of vascular plants, lycophytes (club mosses), horsetails, Ordovician (443-485 MYA): The first fossil evidence of plants on land is from 470 MYA. The first plants were seedless and nonvascular, like moss, hornworts and liverworts, called bryophytes. (52.Springtime, pages 2-7 for activities on the 4 MATERIALS major groups of plants: https:// • computer with internet tra.extension.colostate.edu/stem • 7 sturdy shoeboxes with separate lids -k12/stem-resources/). That • playdough, plaster of Paris, or papier mâché would have provided a carpet of • art supplies (e.g. tape, scissors, markers, glue, green hugging the exposed poster paint, tissue paper, etc.) rock. Further away from water, • craft knife or box cutter (& parent supervision) these early plants would not be • cellophane wrap (party section of store) able to live. There may be a • lots of creativity and imagination connection to the first land THE LAND INVASION — Animals Lumber onto Land 3 and ferns grew to enormous salamanders) were 20 feet! The POWER WORDS sizes, towering almost 100 feet Period also has the fossil • amniote: an animal into the air. The first fossil evidence of the first amniote whose embryo insects are found during the egg. Birds, reptiles, and egg- develops in an amnion Devonian Period. Tetrapods laying mammals have amniote and chorion and has an took their first steps onto land. eggs. Non-amniote eggs must allantois; a mammal, The earliest know tetrapod is be laid in water or damp places. bird, or reptile Tiktaalik rosae (drawing below). Amniote eggs are water proof, • e.g.: Latin exempli and also allow oxygen and gratia, for example carbon dioxide gas exchange. • Sauropsida: group of Pretty neat! amniotes that includes all existing reptiles and Permian (252-299 MYA): birds and their fossil The continents were on their ancestors, including the slow march towards colliding dinosaurs, the and forming the Supercontinent immediate ancestors of Pangaea. The climate was birds drying, and the swamps gave • Synapsida: group of way to more desert-like amniotes that includes This animal is between lobe- landscapes. Conifers are not all existing mammals finned fish and amphibian. The dependent on water for and their fossil hind limbs were stronger and reproduction, like ferns are. The ancestors, including the larger than the front limbs. It plants shifted from former fern “mammal-like reptiles would pull itself along the bottom forests to conifer dominant land. (e.g. Dimetrodon sp. of its aquatic environment, but and Gorgonops sp.) also propel on land. Carboniferous (299-359 MYA): Humid tropical swamps synapsids (formerly dominated this Period. Most of mammal-like reptiles) are the our oil and coal deposits were lineage to (eventually) laid down during this time from mammals, and the the massive vegetation. The Insects continued to diversify, sauropsids (formerly first fossil evidence of conifers and the first fossil evidence of reptiles)are the lineage to (e.g. pine trees) is 300 MYA. piercing and sucking mouthparts dinosaurs, turtles, lizards, are found. crocodiles, and birds. Most amazing are the The Paleozoic Era ended at synapsids and sauropsids. the end of Permian with the These are tetrapods that lead mass extinction event, the to two different lines. The Great Dying. SOME MAMMAL ANCESTORS: Animals grew to enormous sizes. Dragonflies had a 2.5 foot wingspan, millipedes were 6 feet long, 2.5 feet wide, and amphibians (frogs, and THE LAND INVASION — Dioramas 4 Building dioramas are the next summaries of the major POWER WORDS best thing to building a time features of the land during • contrast: strikingly machine! See for yourself what the Paleozoic. Fill in with different from the Paleozoic Era looked like. more specific information. something else Here’s how! • Verify that your website is • diorama: a model from either a university or representing a scene There are two types of natural history museum to with three-dimensional dioramas, each using a ensure that your information figures, either in different orientation of the box. is authentic. For example, miniature or as a large- One is the peephole diorama. the University of Michigan, scale museum exhibit; The advantage is a truly 3D the Smithsonian and the a scenic painting, world. American Museum of Natural viewed through a History have great peephole, in which information. changes in color and • The websites below were direction of illumination selected to give you ideas for simulate changes in the building each diorama’s weather, time of day, landscape, for example, etc. trees (website 8), horsetails • orientation: relative (very similar to bamboo position of something website 9), mountains (website 3, 4, and 5), or The other type of diorama is the water (website 6 and 7). The open box scene. It provides first website has complete directions for how to build a diorama, including selecting good boxes, and the second takes you from beginning to end on a Sierra Mountain 4. build the topography, diorama. It has lots of great the hills, mountains, tips for you. streams, etc. • The basic steps to building a 5. add water to streams, interest in the full scape. diorama: lakes, or oceans Using everyday materials, like 1. select a simple sturdy 6. add vegetation paper, paint, and pebbles, you shoe box with a lid 7. add animals can create wonderful dioramas! 2. paint the outside and • Start with the Cambrian. label what will be inside Take notes and make Directions: 3. Paint the interior of the sketches of the • Each shoebox represents a shoe box with the information as you find it. different Period in the background When you have enough Paleozoic Era: ○ Permian WEBSITES ○ Carboniferous How to: ○ Devonian 1. https://www.youtube.com/results? ○ Silurian search_query=Stephanie+Barnett+diorama ○ Ordovician ○ Cambrian Terrestrial 2. https://www.youtube.com/watch?v=6ganUXUa0sw ○ Cambrian Ocean Topography: • Research information about 3. https://www.youtube.com/watch?v=os1SA2ZpVdE each Period online. The 4. https://www.youtube.com/watch?v=uK0XcoUX9u0 prior two pages are very brief 5. https://www.youtube.com/watch?v=pm-wEpu1yBo THE LAND INVASION — Dioramas 5 information about the poster paint, write the name POWER WORDS climate, landscape, plants of the Period (e.g. • corrugated : material, and animals, sketch what “Cambrian”). surface, or structure you would like your final • The directions are for the shaped into alternate diorama for that Period to open box diorama.
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