BIOL*1050 An Overview of Animal Diversity Lecture 1 PDF

BIOL*1050 An Overview of Animal Diversity Lecture 1 Dr Christine Baes Department of Animal Biosciences Christine Baes Background BSc (AGR) in Guelph, Moscow, Stuttgart MSc (Animal Welfare) in Germany PhD (Quantitative Genetics)...

BIOL*1050 An Overview of Animal Diversity Lecture 1 Dr Christine Baes Department of Animal Biosciences Christine Baes Background BSc (AGR) in Guelph, Moscow, Stuttgart MSc (Animal Welfare) in Germany PhD (Quantitative Genetics) in Germany Currently Department Chair, Professor and Canada Research Chair in Livestock Genomics, Dept. of Animal Biosciences Dozentin at University of Bern, Switzerland Research Interests Genetics, Genomics Methane emissions of livestock Developing novel traits in health, welfare, and efficiency of livestock My Goals 1- Help you learn about the beauty of biology 2- Give you some information you need to succeed in your future courses and maybe more 3- Open your minds to the incredible opportunities in Animal Science 4- Help you succeed in your learning journey at the University of Guelph 5- Survive teaching this class for the first time A note on note-taking See: https://www.cultofpedagogy.com/note-taking/ A note on emails…  the ? I am I would really appreciate any insight you could give me. I am I would really appreciate any insight you could give me.. The moral of the story You are in university, we expect a corresponding level of written communication Salutations are appropriate when writing emails (at least a name is a good idea, when writing to someone with a PhD, write “Dr.”) Use capital letters properly (for help, please see http://grammar.yourdictionary.com/capitalization/10-rules-of- capitalization.html) Colons and semicolons should never be used interchangeably. Use a colon to introduce an item or a series of items (see http://www.grammarbook.com/punctuation/colons.asp for help) Write full sentences I don’t want to make fun of anyone, this is an example used only for educational purposes – I honestly want the best for all of you A Note on ”Is this on the Exam?” ALL material covered in labs, book chapters, and lectures is relevant for exams. This includes ALL spoken, written, and visual forms of information given during this course. What are we going to do today? - Defining “animals” - The history of animals spans more than half a billion years - Animals can be characterized by different types of “body plans” - new molecular and morphological data is reshaping animal phylogeny --> Lecture material refers to material in Chapter 32 of Campbell Biology, pages 725-739 + some additional info… I’d read it if I were you ☺ Defining animals Welcome to your Kingdom!  “Animals are Multicellular organisms are composed of more than one cell, with groups of cells differentiating to take on specialized functions. multicellular, A heterotroph is an organism that eats other plants or animals for energy and nutrients. The term stems from the Greek heterotrophic words hetero for “other” and trophe for “nourishment.” eukaryotes with A eukaryote, is any cell or organism that possesses a clearly defined nucleus. The eukaryotic cell has a nuclear membrane that surrounds the nucleus, in which the well-defined chromosomes tissues that (bodies containing the hereditary material) are located. develop from Tissue is a historically derived biological organizational level between cells and a complete organ. The English word "tissue" derives from the French word "tissu", the past participle of the embryonic verb tisser, "to weave". layers” The three germ layers are the endoderm, the ectoderm, and the mesoderm. Cells in each germ layer differentiate into tissues and embryonic organs. TB Concept 32.1, pg 726  Modification of work by Abigail Pyne Cells in each embryonic / germ layer differentiate into tissues and embryonic organs (process called gastrulation) There are three germ layers: Ectoderm: nervous system and epidermis, among other tissues Mesoderm: muscle cells and connective tissue Endoderm: gut and many internal organs TB Figure 32.2, pg 726 What else makes an animal an animal? Most animals are motile, exhibit active movement at some point in their life (exceptions include coral, sponges, etc.) Most animals reproduce sexually, although some reproduce asexually Animals undergo embryonic development, as a zygote undergo cleavage Viviparous: embryo nourished inside parent, born as live offspring Oviparous: parent lays egg, embryo is nourished by yolk in egg Ovovivoparous: egg remains inside parent until ready to hatch, embryo is nourished by yolk Homeobox genes are common to almost all animals and control development of the body Hox genes highly conserved, but produce diverse morphology The history of animals  “The history of There are 1.3 million extant (surviving) species of animals, but estimates of the actual number are animals spans far higher. Research suggests that the common ancestor of all more than half a extant animal species lived about 770 million years ago – sponges originated about 700 million years billion years” ago. Sponges, like, corals, are immobile aquatic (… that’s over invertebrates, but they are otherwise 500,000,000 completely different years ago…) TB Concept 32.2, pg 727 See https://oceanservice.noaa.gov/facts/sponge.html  The Neoproterozoic Era (1 Billion - 542 million years ago) Mistaken Point, on the Avalon Peninsula of Newfoundland, contains some of the oldest fossils that date to approximately 565 million years ago (takes 40 hours to get there by car…) Fossils dating to 560 million years ago document the earliest known macroscopic animals TB Figure 32.4, pg 728  The Paleozoic Era (542 – 251 million years ago) - Arthropods were on land about 450 mya - Vertrabrates on land 365 mya - amphibians (frogs, salamanders) - amniotes (reptiles, birds, mammals) - Insects and plants were influencing each- others evolution by 302 mya Paleontologists have found the oldest fossils of about half of all extant animal phyla in the Burgess Shale in Yoho National Park in British Columbia TB Figure 32.6, pg 729 The Mesozoic Era (251 – 65.5 million years ago) - Animal phyla spread into new habitats - Coral reefs forming - Origin of wings - Dinosaurs - First tiny mammals https://iceage.museum.state.il.us/content/ when-have-ice-ages-occurred The Cenozoic Era (65.5 million years ago - now) - Mass extinction of terrestrial and marine animals - Large, non-flying dinosaurs and marine reptiles disappeared - Rise of large, mammalian herbivores and predators - Global climate cooled Survey (Poll Everywhere) Put the eras in order from oldest to youngest Survey (Poll Everywhere) True or false: I know what a correlation coefficient is and how to estimate one. If no: see Chapter 32, page 731 and complete the Scientific Skills Exercise If yes, see Chapter 32, page 731 and complete the Scientific Skills Exercise anyway, it’s fantastic practice ☺ “Body Plans”  Morphology is the study of the size, shape, and Animals differ structure of animals, plants, and microorganisms and of the relationships of their constituent parts. greatly in Body plans provide a way to compare and contrast key animal features. morphology, but Animal body plans can evolve over time, emerge can can be and never changed again, or change over and over. Similar body forms may evolve independantly characterized by Some body features are lost over the course of relatively few evolution, making some closely related species look very different from eachother. “body plans” TB Concept 32.3, pg 732  Dorsal = top Ventral = bottom Anterior = front Posterior = back Most bilateral animals have a central nervous system to coordinate complex movements. Fossil evidence indicates that these two kinds of symmetry have been present for at least 550 million years Concept in TB Figure 32.8, pg 733 Tissues Ectoderm Endoderm Bilaterally symmetrical animals also have a Mesoderm (triploblastic vs. diploblastic) Forms muscles and other organs between the digestive tract and outer covering of the animals Body Cavities Nearly all animals have body cavities, fluid-filled spaces between different tissue layers Diverse functions: structural support, internal transport systems, gas exchange, waste removal Larger animals have a coelom (pron. “See-lum”, from the Greek koilos, “hollow”) Coelem = hydrostatic skeleton for earthworms Allows organs to grow and move independently  Hemocoel: Cavity between endoderm and mesoderm, filled with hemolymph. Involved with internal circulation, nutrient transport, and waste removal but can also function as a hydrostatic skeleton in some animals. Hemolymph is analogous to blood and is circulated throughout the body cavity in an open system by the heart. Many animals have both types of body cavities, a coelom and a hemocoel. Some triploblastic animals are compact and lack a body cavity altogether, rely on diffusion across the body surface TB Figure 32.9, pg 734  Many animals can be described as having one of two developmental modes: - protostome development, or - deuterostome development. Protostomes In organisms that develop mouths are deuterostomes, from the first the anus develops opening in the from the second gastrula. opening in the As the embryo gastrula. develops, the Coelom develops mesoderm splits from two pouches in down the the mesoderm. middle to form the coelom. TB Figure 32.10, pg 735 Animal Phylogeny  Zoologists currently recognize about three dozen Views of animal phyla of extant animals (15 are shown in Figure 32.11 on the next slide phylogeny Body plans provide a way to compare and contrast key animal features. continue to be Animal body plans can evolve over time, emerge shaped by new and never change again, or change over and over. Similar body forms may evolve independently molecular and Some body features are lost over evolution, making morphological some closely related species look very different from eachother. data TB Concept 32.4, pg 735  All animals share a common ancestor. Sponges are basal animals. Eumetazoa is a clade of animals with true tissues Most animal phyla belong to the clade Bilateria There are three major clades of bilaterian animals “deuterostome” has a dual meaning: those with a deuterostomal developmental pattern are not members of clade Deuterostomia  TB Figure 32.11, pg 736 What did we do today? An overview of Animal Diversity: - Animals are multicellular, heterotrophic eukaryotes with tissues that develop from embryonic layers - The history of animals spans more than half a billion years - Animals can be characterized by “body plans” - Views of animal phylogeny continue to be shaped by new molecular and morphological data - Wednesday: Dr. Alexandra Harlander (a fantastic professor!) Learning Questions 32.1.1: Summarize the main stages of animal development. What family of control genes plays a major role? 32.2.1: Put the following milestones in animal evolution in chronological order from oldest to most recent: (a) origin of mammals, (b) earliest evidence of terrestrial arthropods, (c) Ediacaran fauna, (d) extinction of large, nonflying dinosaurs. 32.2.2: Explain what is represented by the red-colored portion of the branch leading to animals. (See Chapter 26, “Interpreting Phylogenetic Trees,” to review phylogenetic tree diagrams.) 32.3.1: Why would an animal lacking any body cavities tend to be small or flat? 32.3.2: Compare three aspects of the early development of a snail (a mollusc) and a human (a chordate). 32.3.3: Evaluate this claim: Ignoring the details of their specific anatomy, worms, humans, and most other triploblasts have a shape analogous to that of a doughnut.