The Mesozoic Era

Your Name: Alex Reyer

Laboratory Title: Dinosaur Finger Puppets

Laboratory Objectives:  Students will understand the different periods of the Mesozoic Era  Students will learn the different characteristics of each period  Students will learn about the influences of dinosaurs in the Mesozoic Era  Students will learn brief facts about two different dinosaurs (T. Rex and Brachiosaurus)

Benchmark(s) Addressed:

Life Science

CCG: Organisms: Understand the characteristics, structure, and functions of organisms.

 SC.05.LS.01 Group or classify organisms based on a variety of characteristics.  SC.05.LS.03.01 Associate specific structures with their functions in the survival of the organism

Materials and Cost: This lab is based around a power point lesson to teach children about the aspects of the Mesozoic era. The lab is meant to be fun and allow children to connect what they learned about dinosaurs and the different periods to a visual project.

Intial Prep- 6 hours for power point/ research Prep. time- 2 minutes to load power point Instruction time- 45 minutes, lecture and project Clean up time- 5 minutes to throw away scraps and collect scissors and markers

Assesment: 1) Summarize the three periods of the Mesozoic era. What were characteristics of each time period? How were they similar? How were they different? 2) What physical characteristics do dinosaurs have in common? What characteristics vary among dinosaurs? 3) What period did the first flowered plants appear? 4) What is the Mesozoic Era known as?

Materials: Power Point on Mesozoic Era, Worksheets – T. Rex and Brachiosaurus, Scissors, Markers Procedure: 1. Power Point (30 minutes) Mesozoic Era and three periods ( Triassic, Jurassic, Cretaceous) 2. Distribute worksheets, scissors, markers 3. Have each student cut out designated dinosaur (read about individual facts) and color to their preference.

Background Information: The Mesozoic Era

The Mesozoic is divided into three time periods: the Triassic (245-208 Million Years Ago), the Jurassic (208-146 Million Years Ago), and the Cretaceous (146-65 Million Years Ago). Mesozoic means "middle animals", and is the time during which the world fauna changed drastically from that which had been seen in the Paleozoic. Dinosaurs, which are perhaps the most popular organisms of the Mesozoic, evolved in the Triassic, but were not very diverse until the Jurassic. Except for birds, dinosaurs became extinct at the end of the Cretaceous. Some of the last dinosaurs to have lived are found in the late Cretaceous deposits of Montana in the United States. The Mesozoic was also a time of great change in the terrestrial vegetation. The early Mesozoic was dominated by ferns, cycads, ginkgophytes, bennettitaleans, and other unusual plants. Modern gymnosperms, such as conifers, first appeared in their current recognizable forms in the early Triassic. By the middle of the Cretaceous, the earliest angiosperms had appeared and began to diversify, largely taking over from the other plant groups. Triassic Period

Roughly 248 million years ago (mya), the Permo-Triassic extinction occurred. This is the largest extinction known. About 95% of all species and about 60% of the genera died out, including many marine animals (like the trilobite). The cause of the Permian extinction might have been global cooling, volcanic eruptions, or a decrease in the continental shelf area during the formation of pangaea. This catastrophic extinction and continental rearrangement opened the way for the rise of the dinosaurs and mammals. There were no dinosaurs at the beginning of the Triassic, but there were many amphibians and some reptiles and dicynodonts (like Lystrosaurus). During the early Triassic, corals appeared and ammonites recovered from the Permian extinction. Seed plants dominated the land; in the Northern hemisphere, conifers flourish. Glossopteris was the dominant southern hemisphere tree during the Early Triassic period. During the late Triassic, 220 million years ago, the first true mammals appeared, like Eozostrodon. Some scientists believe that mammals evolved from a group of extinct mammal-like reptiles, Theriodontia, which were Therapsids. These primitive mammals were tiny and are thought to have been nocturnal. The earliest-known turtle, Proganochelys, appeared during the late Triassic. Turtles, frogs, salamanders, lizards (including sphenodonts & snakes), and pterosaurs first appeared in the Triassic. Also in the Triassic was Pseudosuchia, possible ancestor of Archaeopteryx. Aetosaurs like Desmatosuchus lived during the late Triassic period. Insects began to undergo complete metamorphosis from larva through pupa to adult. In the seas, ichthyosaurs, marine reptiles, appeared. The Triassic's climate was generally hot and dry, with strong seasonality. The formation of the super continent of Pangaea at the beginning of the Triassic, 220 million years ago, decreased the amount of shoreline, formed mountains, and gave the interior of the super continent a dry, desert-like terrain. The polar regions were moist and temperate.

Jurassic Period

Great plant-eating dinosaurs roaming the earth, feeding on lush growths of ferns and palm-like cycads and bennettitaleans. . . smaller but vicious carnivores stalking the great herbivores. . . oceans full of fish, squid, and coiled ammonites, plus great ichthyosaurs and long-necked plesiosaurs. . . vertebrates taking to the air, like the pterosaurs and the first birds. . . this was the Jurassic Period, beginning approximately 210 million years ago and lasting for 70 million years of the Mesozoic Era. It is quite true that the dinosaurs dominated the land fauna -- although many of the dinosaurs featured in "Jurassic Park", such as Triceratops and Tyrannosaurus rex, did not evolve until after the Jurassic was over. The largest dinosaurs of the time -- in fact, the largest land animals of all time -- were the gigantic sauropods, such as the famous Diplodocus (pictured at lower left), Brachiosaurus and Apatosaurus. Other herbivorous dinosaurs of the Jurassic included the plated stegosaurs. Predatory dinosaurs of the Jurassic included fearsome carnosaurs such as Allosaurus, small, fast coelurosaurs, and ceratosaurs such as Dilophosaurus. The Jurassic also saw the origination of the first birds, including the well- known Archaeopteryx, probably from coelurosaurian ancestors. But there was more to life than dinosaurs! In the seas, the fishlike ichthyosaurs were at their height, sharing the oceans with the plesiosaurs, with giant marine crocodiles, and with modern-looking sharks and rays. Also prominent in the seas were cephalopods -- relatives of the squids, nautilus, and octopi of today. Jurassic cephalopods included the ammonites, with their coiled external shells (upper left), and the belemnites, close relatives of modern squid but with heavy, calcified, bullet-shaped, partially internal shells. Among the plankton in the oceans, the dinoflagellates became numerous and diverse, as did the coccolithophorids (microscopic single-celled algae with an outer covering of calcareous plates). Land plants abounded in the Jurassic, but floras were different from what we see today. Although Jurassic dinosaurs are sometimes drawn with palm trees, there were no palms, or any other flowering plants, at least as we know them today, in the Jurassic. Instead, ferns, ginkgoes, bennettitaleans or "cycadeoids", and true cycads -- like the living cycad pictured at the above right -- flourished in the Jurassic. Conifers were also present, including close relatives of living redwoods, cypresses, pines, and yews. Creeping about in this foliage, no bigger than rats, were a number of early mammals.

Cretaceous Period

The Cretaceous is usually noted for being the last portion of the "Age of Dinosaurs", but that does not mean that new kinds of dinosaurs did not appear then. It is during the Cretaceous that the first ceratopsian and pachycepalosaurid dinosaurs appeared. Also during this time, we find the first fossils of many insect groups, modern mammal and bird groups, and the first flowering plants. The breakup of the world- continent Pangaea, which began to disperse during the Jurassic, continued. This led to increased regional differences in floras and faunas between the northern and southern continents. The end of the Cretaceous brought the end of many previously successful and diverse groups of organisms, such as non-avian dinosaurs and ammonites. This laid open the stage for those groups which had previously taken secondary roles to come to the forefront. The Cretaceous was thus the time in which life as it now exists on Earth came together. No great extinction or burst of diversity separated the Cretaceous from the Jurassic Period that had preceded it. In some ways, things went on as they had. Dinosaurs both great and small moved through forests of ferns, cycads, and conifers. Ammonites, belemnites, other molluscs, and fish were hunted by great "marine reptiles," and pterosaurs and birds flapped and soared in the air above. Yet the Cretaceous saw the first appearance of many lifeforms that would go on to play key roles in the coming Cenozoic world.

Perhaps the most important of these events, at least for terrestrial life, was the first appearance of the flowering plants, also called the angiosperms or Anthophyta. First appearing in the Lower Cretaceous around 125 million years ago, the flowering plants first radiated in the middle Cretaceous, about 100 million years ago. By the close of the Cretaceous, a number of forms had evolved that any modern botanist would recognize.

At about the same time, many modern groups of insects were beginning to diversify, and we find the oldest known ants and butterflies. Aphids, grasshoppers, and gall wasps appear in the Cretaceous, as well as termites and ants in the later part of this period. Another important insect to evolve was the eusocial bee, which was integral to the ecology and evolution of flowering plants. The Cretaceous also saw the first radiation of the diatoms in the oceans (freshwater diatoms did not appear until the Miocene).

The most famous, if not the largest, of all mass extinctions marks the end of the Cretaceous Period, 65 million years ago. As everyone knows, this was the great extinction in which the dinosaurs died out. (Except for the birds, of course.) The other lineages of "marine reptiles", such as the ichthyosaurs, plesiosaurs, and mosasaurs, also were extinct by the end of the Cretaceous, as did the flying pterosaurs -- although some, like the ichthyosaurs, were probably extinct a little before the end of the Cretaceous. Many species of foraminiferans went extinct at the end of the Cretaceous, as did the ammonites. But many groups of organisms, such as flowering plants, gastropods and pelecypods (snails and clams), amphibians, lizards and snakes, crocodilians, and mammals "sailed through" the Cretaceous-Tertiary boundary, with few or no apparent extinctions at all.