Locomotor Evolution in the Earliest Cetaceans: Functional Model, Modem Analogues, and Paleontological Evidence
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Thomas Jefferson Meg Tooth
The ECPHORA The Newsletter of the Calvert Marine Museum Fossil Club Volume 30 Number 3 September 2015 Thomas Jefferson Meg Tooth Features Thomas Jefferson Meg The catalogue number Review; Walking is: ANSP 959 Whales Inside The tooth came from Ricehope Estate, Snaggletooth Shark Cooper River, Exhibit South Carolina. Tiktaalik Clavatulidae In 1806, it was Juvenile Bald Eagle originally collected or Sculpting Whale Shark owned by Dr. William Moroccan Fossils Reid. Prints in the Sahara Volunteer Outing to Miocene-Pliocene National Geographic coastal plain sediments. Dolphins in the Chesapeake Sloth Tooth Found SharkFest Shark Iconography in Pre-Columbian Panama Hippo Skulls CT- Scanned Squalus sp. Teeth Sperm Whale Teeth On a recent trip to the Academy of Natural Sciences of Drexel University (Philadelphia), Collections Manager Ned Gilmore gave John Nance and me a behind -the-scenes highlights tour. Among the fossils that belonged to Thomas☼ Jefferson (left; American Founding Father, principal author of the Declaration of Independence, and third President of the United States) was this Carcharocles megalodon tooth. Jefferson’s interests and knowledge were encyclopedic; a delight to know that they included paleontology. Hand by J. Nance. Photo by S. Godfrey. Jefferson portrait from: http://www.biography.com/people/thomas-jefferson-9353715 ☼ CALVERT MARINE MUSEUM www.calvertmarinemuseum.com 2 The Ecphora September 2015 Book Review: The Walking 41 million years ago and has worldwide distribution. It was fully aquatic, although it did have residual Whales hind limbs. In later chapters, Professor Thewissen George F. Klein discusses limb development and various genetic factors that make whales, whales. This is a The full title of this book is The Walking complicated topic, but I found these chapters very Whales — From Land to Water in Eight Million clear and readable. -
Not for Sale
NOT FOR SALE © Roberts and Company Publishers, ISBN: 9781936221448, due August 23, 2013, For examination purposes only FINAL PAGES NOT FOR SALE The earliest whales, such as the 47-million-year-old Ambulocetus, still had legs. Their anatomy gives us clues to how whales made the transition from land to sea. © Roberts and Company Publishers, ISBN: 9781936221448, due August 23, 2013, For examination purposes only FINAL PAGES NOT FOR SALE Walking 1 Whales Introducing Evolution ne of the best feelings paleontologists can ever have is to realize that they’ve just found a fossil that will fll an empty space in our understanding Oof the history of life. Hans Thewissen got to enjoy that feeling one day in 1993, as he dug a 47-million-year-old fossil out of a hillside in Pakistan. As he picked away the rocks surrounding the FIGURE 1.1 bones of a strange mammal, he suddenly realized what he had Paleontologist Hans Thewissen has discovered many of the bones of found: a whale with legs. Ambulocetus in Pakistan. A hundred million years ago, not a single whale swam in all the world’s oceans. Whales did not yet exist, but their ancestors did. At the time, they were small, furry mammals that walked on land. Over millions of years, some of the descendants of those ancestors underwent a mind-boggling transformation. They lost their legs, traded their nostrils for a blowhole, and became crea- tures of the sea. This profound change was the result of evolution. 3 © Roberts and Company Publishers, ISBN: 9781936221448, due August 23, 2013, For examination purposes only FINAL PAGES NOTThis bookFOR is an introduction to that SALE process. -
A Brief History of Whale Evolution: As Supported by The
A Brief History of Whale Evolution As Supported By the Fossil Record BIOB 272 – Genetics and Evolution Presented by Mindy Flanders Presented for Rick Henry December 8, 2017 Cetaceans—whales, dolphins, and porpoises—are so different from other animals that, until recently, scientists were unable to identify their closest relatives. As any elementary student knows, a whale is not a fish. That means that despite the similarities in where they live and how they look, whales are not at all like salmon or even sharks. Carolus Linnaeus, known for classifying plants and animals, noted in the 1750s that “whales breathe air through lungs not gills; are warm blooded; and have many other anatomical differences that distinguish them from fish” (Prothero, 2015). Other characteristics cetaceans share with all other mammals are: they have hair (at some point in their life), they give birth to live young, and they nurse their young with milk. This implies that whales evolved from other mammals and, because ancestral mammals were land animals, that whales had land ancestors (Thewissen & Bajpai, 2001). But before they had land ancestors they had water ancestors. The ancestors of fish lived in water, too. Up until 375 million years ago (mya), everything other than plants and insects lived in water, but it was around that time that fish and land animals began to diverge. A series of fossils represent the fish-to-tetrapod transition that occurred during the Late Devonian Period 359-383 mya (Herron & Freeman, 2014). In search of a new food source, or to escape predators more than twice their size (Prothero, 2015), the first tetrapods pushed themselves out of the swamps and began to live on land (Switek, 2010). -
Pakicetus Were Similar to Land Images
S u p p l e m e n t Whale Ears By Dr. Carl Werner A p p e n d i x 1 S u p p l e m e n t S u p p l e m e n t First Edition Version 7 Introduction © Copyright May 2014, Audio Visual Consultants, Inc. Author’s Note: This supplement to Appen- Before proceeding, it would be best to first Copyright © 2014 by Carl Werner. All rights reserved. dix F of Evolution: The Grand Experiment (3rd read Chapter 13 and Appendix F of the 3rd No part of this book may be used or reproduced in any edition) provides important information about edition of Evolution: The Grand Experiment. manner whatsoever without written permission of the the function and gross anatomy of the external Next, it is very important to read the press publisher except in the case of brief quotations in articles and middle ear of land animals, whales and release at TheGrandExperiment.com under the and reviews. For more information contact Dr. Werner purported “walking whales.” This material was “Whale Evolution” tab. Finally, take a brief through the Grand Experiment web page. not included in the book, the e-book or the video look at the chart below detailing the classifica- series because of space considerations. tion of whales and dolphins in the mammal order called Cetacea. You will then be prepared Please visit our web site for other great titles: to better understand this important information. www.TheGrandExperiment.com Cetacea Odontocete Mysticete (Cetacea with Teeth) (Cetacea without Teeth) Toothed Whales Toothed Dolphins Baleen Whales -Orca Whale -Bottlenose Dolphin -Humpback Whale -Sperm Whale -Spinner Dolphin -Gray Whale -Beluga Whale -Atlantic Spotted Dolphin -Right Whale -Etc. -
Evolution and Development of Cetacean Appendages Across the Cetartiodactylan Land-To-Sea Transition
EVOLUTION AND DEVELOPMENT OF CETACEAN APPENDAGES A dissertation submitted to Kent State University in partial fulfillment of the requirements for the degree of Doctor of Philosophy by Lisa Noelle Cooper December, 2009 Dissertation written by Lisa Noelle Cooper B.S., Montana State University, 1999 M.S., San Diego State University, 2004 Ph.D., Kent State University, 2009 Approved by _____________________________________, Chair, Doctoral Dissertation Committee J.G.M. Thewissen _____________________________________, Members, Doctoral Dissertation Committee Walter E. Horton, Jr. _____________________________________, Christopher Vinyard _____________________________________, Jeff Wenstrup Accepted by _____________________________________, Director, School of Biomedical Sciences Robert V. Dorman _____________________________________, Dean, College of Arts and Sciences Timothy Moerland ii TABLE OF CONTENTS LIST OF FIGURES ........................................................................................................................... v LIST OF TABLELS ......................................................................................................................... vii ACKNOWLEDGEMENTS .............................................................................................................. viii Chapters Page I INTRODUCTION ................................................................................................................ 1 The Eocene Raoellid Indohyus ........................................................................................ -
The Evolution of Whales
The Evolution of Whales Geology 331 Whales Prothero, 2007 Evolution of Whales 1990s Evolution of Whales 2000s Prothero, 2007 Archaeocetes The two major groups of living whales: Mysticetes (baleen) and Odontocetes (toothed) Blue Whale, Humpback Whale, Sperm Whale, and Killer Whale Whale baleen Tertiary Outcrops Yielding Fossil Whales in Asia Closing of the Tethys Sea during the Cenozoic Indohyus: 48 MY old Pakicetus: 50 MY old Ambulocetus: 49 MY old Basilosaurus: 37 MY old Dorudon: 35 MY old Pakicetus: 50 MY old Size comparison with a modern coyote skull Ambulocetus: 49 MY old Ambulocetus in action Reconstruction of the fossil whale Ambulocetus from the Eocene of Pakistan (~ 49 million years ago). Ambulocetus was discovered in 1994. In this artists reconstruction, Ambulocetus is shown living like a crocodile, hunting land mammals near the shore. Rodhocetus: 46 MY old The ankle bones of Rodhocetus are more similar to artiodactyls (even-toed ungulates) than the traditional mesonychian ancestor. Ocean Hall, Smithsonian Institution Kutchicetus: 45 MY old 5 2 3 1 4 15 MY of evolution during the Eocene Evolutionary Order: 1, Pakicetus; 2, Ambulocetus; 3, Rodhocetus; 4, Kutchicetus; 5, Dorudon Basilosaurus: 37 MY old Ankle, foot, and toes of Basilosaurus excavated in Wadi Hitan, Egypt. The foot as shown is approximately 12 cm long. Photograph ©1991 Philip Gingerich. Phil Gingerich’s work on fossil whales http://www.youtube.com/watch?v=I2C-3PjNGok Dr. B. Holly Smith working at the base of the tail at a Basilosaurus excavation in Wadi Hitan, Egypt. We are particularly interested in this part of the skeleton because this is where the reduced hind limbs, feet, and toes are found. -
Investigate How Whales Evolved from Living on Land to Life in the Sea
WHALES: Giants of the Deep Activities for Grades 9-12 Investigate How Whales Evolved from Living on Land to Life in the Sea Overview NYS Science Core Curriculum Before Your Visit: Students will discuss what makes a whale a LE 3.1a: The basic theory of mammal and read about the placement of whales in the Tree of Life. biological evolution states that the Earth’s present-day species During Your Visit: Students will observe features and gather developed from earlier, distinctly evidence to support the claim that the ancestors of present-day different species. whales lived on land. After Your Visit: Students will use the evidence collected from observing fossil specimens and reading labels at the Museum to write an explanation of how whales evolved from terrestrial to aquatic animals. Background for Educators Recent molecular and fossil discoveries show the close relationship of whales to even-toed ungulates, the artiodactyls (i.e. cow, sheep, hippopotamus). In fact, their closest relatives are hippos. The ancestors of whales lived on land about 50 million years ago. Known collectively as Archeocetes, or ancient whales, they might have moved into water in part because of environmental factors – a hot period on Earth. Once whales adapted to water, they diversified and came to inhabit the world’s oceans. Almost 80 spe- cies of Cetaceans are alive today. Scientists study both living and fossil species, and use both anatomy and genetic evidence to understand how these intelligent mammals evolved and where they fit in the Tree of Life. Additional information about the evolution of whales: http://evolution.berkeley.edu/evolibrary/article/evograms_03 Before Your Visit Activity 1: Discussion of What Makes a Whale a Mammal Plan how your students will explore the Whales exhibition Ask students to work in groups of two or three to list all basic using the worksheets. -
Lec 2.06 Evidence for Evolution
Indohyus Ambulocetus “Walking Whale” How did Ambulocetus make its living? Typical mammalian ear bones Bottle-nosed dolphin Tursiops truncatus Thick, shell- like auditory bullae Detached auditory bullae Involucrum Characteristics of Auditory Bullae in Mammals 1) All mammals except those listed below: Auditory bullae fused used with skull Relatively thin No involucrum 2) Indohyus: Fused used with skull Slightly thickened Slight involucrum 3) Ambulocetus: Fused used with skull Thick Involucrum 4) Modern whales and dolphins (Cetaceans): Auditory bullae detached (except in some baleen whales) Thick, shell-like Involucrum Basilosaurids (Dorudon) Basilosaurids (Dorudon) Right Whale F Plan of bones in the forelimbs of all vertebrates are essentially the same A one-month old embryo What kind of creature is this? Gill arches Later in development will be covered with hair Fore Limb Tail Hind Limb The same embryo 8 months later Vestigial Traits are Common Vestigial trait is a structure found in greatly reduced, often nonfunctional, form that is homologous to function structures found in other species Example: Hair and gill arches in developing dolphins Example: Long tail and gill arches in humans Example: Pelvic girdle structures in cetaceans Vestigial Traits are Common Vestigial trait is a structure found in greatly reduced, often nonfunctional, form that is homologous to function structures found in other species Example: Dewclaws in terrestrial vertebrates (e.g., hoofed mammals) Vestigial Traits are Common Vestigial trait is a structure found in -
Evidence for Evolution
Fossils Examples Genetics Refs Unit 2: Transmission Genetics Lecture 2.6: Evidence for Evolution John D. Nagy BIO 181: General Biology for Majors, Scottsdale Community College 2020 Revision John Nagy Lec 2.6: Evidence for Evolution 1/36 Fossils Examples Genetics Refs Outline 1 Some interesting fossils Synapomorphies Body plan Vestiges Timeline 2 Examples Mammals Avians Tetrapods 3 Molecular Genetic Evidence 4 Literature cited John Nagy Lec 2.6: Evidence for Evolution 2/36 Fossils Examples Genetics Refs Synapomorphies Body plan Vestiges Timeline What kind of creature is this? John Nagy Lec 2.6: Evidence for Evolution 3/36 Fossils Examples Genetics Refs Synapomorphies Body plan Vestiges Timeline Indohyus \Indohyus was an animal similar in size to a cat but quite different from a cat in shape. It had a long snout and a long tail and long slender limbs. At the end of each limb, there were four or five toes that ended in hoof, similar to that of a deer" [11, pg. 274]. The ear bones have a \thickened wall. called the involucrum [which] is present in all cetaceans, fossil and recent. The involucrum is not present in other mammals, except for one: Indohyus" [11, pg. 275]. John Nagy Lec 2.6: Evidence for Evolution 4/36 Fossils Examples Genetics Refs Synapomorphies Body plan Vestiges Timeline Ventral (underneath) view of dog cranium The ear bones Thewissen et al. [11] refer to are auditory bullae. So Indohyus is a racoon-shaped mammal with hooves like a deer and ear bones like a whale. John Nagy Lec 2.6: Evidence for Evolution 5/36 Fossils Examples Genetics Refs Synapomorphies Body plan Vestiges Timeline What kind of creature is this? John Nagy Lec 2.6: Evidence for Evolution 6/36 Fossils Examples Genetics Refs Synapomorphies Body plan Vestiges Timeline Ambulocetus Ambulocetus was \roughly the size of a large male sea lion" [11, pg. -
Walking with Whales.Pdf
news and views Walking with whales Christian de Muizon Whales must have evolved from land-based mammals, but fossil evidence of some of the steps in between has been patchy. Newly discovered skeletons with legs fill in the gaps. n page 277 of this issue, Thewissen and colleagues1 describe their discovery of u.p. Opartial fossil skeletons from the earliest cetaceans — a group of mammals that today consists of whales, porpoises and dolphins. The fossils, which are some 50 million years Diacodexis old and were found in Pakistan, take us a huge step forwards in understanding the origins and evolutionary relationships of Phenacodus Pachyaena whales. Until now, the limbs of all known u.p. early cetaceans reflected an amphibious or 2–6 wholly aquatic lifestyle . But the newly Pakicetus discovered fossils show that the first whales l.p. were fully terrestrial, and were even efficient runners. They also reveal that cetaceans are Pakicetus Diacodexis Sus more closely related to the oldest known even-toed ungulates — a group of hoofed Ambulocetus mammals that includes cows, hippos, pigs, Figure 2 Ankle bones (astragali) of hoofed 17 camels and giraffes — than to any other Pelvis and mammals and primitive whales. Phenacodus , hindlimb mammals. These conclusions are based on Dorudon a primitive ungulate, had an unspecialized solid anatomical data, and contradict the ankle bone that resembles that of Pachyaena17, previous hypotheses of both palaeontolo- Pelvis and a mesonychian ungulate from 50 million years gists and molecular biologists7–10. hindlimb Balaena ago. The double-pulleyed astragali of Pakicetus All of the mammals that existed in the early (one of the fossil cetaceans described by Tertiary — some 65–50 million years ago — Figure 1 The evolutionary route to a whale. -
Lesson 1 Where Did the Whales Come From?
G4 U4 L1 LESSON 1 Where did the Whales Come From? Lesson at a Glance Students investigate information about the development of today’s whales during the last 60 million years. The readings take students from the whale’s early terrestrial ancestors to the aquatic mammals of today. Lesson Duration Related HCPSIII Two 60-minute periods Benchmark(s): Essential Question(s) Science SC.4.1.2 What is a fossil? Differentiate between an How did whales evolve from land to sea animals? observation and an inference Key Concepts Science SC.4.5.1 • Fossils are preserved remains of plants and animals that Compare fossils and lived thousands to millions of years ago. living things • Fossil remains indicate that whales evolved from Language Arts LA.4.2.2 hoofed land animals. Use organizational patterns (e.g., sequential, cause and Instructional Objectives effect) to access and • I can differentiate between an observation and an inference. understand information. • I can compare fossil evidence and living things to identify similarities and differences. • I can fi nd clues to chronological order to access and understand information. • I can use information to build a timeline. 1 G4 U4 L1 Assessment Tools Benchmark Rubric: Topic Scientifi c Knowledge Differentiate between an observation and an Benchmark SC.4.1.2 inference Rubric Advanced Profi cient Partially Profi cient Novice Explain the difference Differentiate between Provide examples Defi ne an observation between an observation an observation and an of observations and and an inference and an inference -
A New Eocene Archaeocete (Mammalia, Cetacea) from India and the Time of Origin of Whales
Proc. Natl. Acad. Sci. USA Vol. 95, pp. 15464–15468, December 1998 Evolution A new Eocene archaeocete (Mammalia, Cetacea) from India and the time of origin of whales SUNIL BAJPAI* AND PHILIP D. GINGERICH†‡ *Department of Earth Sciences, University of Roorkee, Roorkee 247667, Uttar Pradesh, India; and †Museum of Paleontology and Department of Geological Sciences, University of Michigan, Ann Arbor, MI 48019-1079 Communicated by Elwyn L. Simons, Duke University Primate Center, Durham, NC, October 15, 1998 (received for review October 9, 1998) ABSTRACT Himalayacetus subathuensis is a new pakicetid Family Pakicetidae Gingerich & Russell 1990 archaeocete from the Subathu Formation of northern India. Himalayacetus subathuensis, new genus and species The type dentary has a small mandibular canal indicating a Etymology. Himalaya, Sanskrit, place of snow and cetus, lack of auditory specializations seen in more advanced ceta- Greek (masculine), whale; subathuensis refers to the Subathu ceans, and it has Pakicetus-like molar teeth suggesting that it Formation and Subathu type section in the Himalayan foothills fed on fish. Himalayacetus is significant because it is the oldest yielding the fossil described here. archaeocete known and because it was found in marine strata Holotype. Left dentary with molar teeth M2–3 (Figs. 1b and associated with a marine fauna. Himalayacetus extends the 2 a and b), Roorkee University Vertebrate Paleontology fossil record of whales about 3.5 million years back in geo- Laboratory [RUSB] specimen 2003, collected by A. Sahni, J.-J. logical time, to the middle part of the early Eocene ['53.5 Jaeger, V. Courtillot, and E. Buffetaut during a joint Panjab million years ago (Ma)].