15 May In this assignment you will practice applying and gain further knowledge about information form the lectures, Tree of Life Part I? and Tree of Lif
In this assignment you will practice applying and gain further knowledge about information form the lectures, “Tree of Life Part I” and “Tree of Life Part II”.
1000 WORDS
This assignment is due May 19th by 11:59 pm.
You will visit two websites, explore them, and answer some questions as you do.
Whenever I ask you to answer questions, please do so in the same document, and make sure to include the questions with your answers.
Part Ia – Exploring Taxonomy – Relative Taxonomic Diversity
1) Open the lecture slide pdf for the lecture entitled "Patterns of Biodiversity – Relative Taxonomic Diversity". It's in Unit 1, 4 – Patterns of Biodiversity – Species in the lecture folder. It is not a narrated lecture. You will be reading through the slides to answer the questions below.
2) We will start by focusing on the major groups (animals, fungi, plant, protists, bacteria). For each group there are estimates of the total number of species already described and the predicted total alive today. For the "animals" you are going have to add values from the slides with information on vertebrates, crustaceans, arachnids, round worms, and insects.
a) What is the major group with the most described number of species? What are the described and predicted values?
b) Some groups are better described than others. Which major group has the lowest ratio of described to predicted species?
3) Please answer the same questions as in question 2, but focus on the subgroups within animals.
4) What was the main take-away you got from answering these questions?
Part Ib – Exploring Taxonomy – Categorizing Life
1) In the “Tree of Life Web Project” website, go to the “Browse” menu and choose the “Root” menu item.
2) I am going to have you move up the categories from the root to humans. I am going to give you a sequence of links to follow. In the root, notice there are three main branches at the top of the page that are highlighted as links. Each branch has a taxonomic designator and then in parentheses a description of what’s in the group. I am going to provide you with one descriptor for each branch point.
So starting at the root follow this sequence: animals, metazoa, vertebrates, vertebrates, vertebrates and relatives, hagfishes and vertebrates, lampreys and jawed vertebrates, jawed vertebrates, lobbed-finned fishes and four-legged vertebrates, mammals, mammals, mammals and their extinct relatives, mammals and their extinct relatives, mammalia, placental mammals, monkeys, humans, humans, humans, modern humans.
You should end with Homo sapiens.
Please answer the following questions:
1) List the containing groups for Homo sapiens. All you have to do is go to the right-hand panel and they are listed there.
2) For three containing groups use Wiki to find the shared derived characteristics that set that group apart from other groups.
3) Pick any species you are interested in and search Wikipedia for it’s taxonomic classification. What is the classification for the species you picked? (Note: I do not trust wiki for everything. I stay away from it for “controversial” subjects like climate change or evolution. There are too many people editing wiki without good scientific knowledge of subjects like this. Taxonomic classification is generally well done on Wiki.)
Part II – Exploring Phylogenetics – The Tree of Life
1) Please go to the Evogeneao website (www.evogeneao.com) and go to the “Learn” menu and choose the “Tree of Life” menu item.
2) Read the first four of five sections of text on that page.
3) Answer the following questions. Keep your answers to a sentence or two. (DO NOT cut & paste answers from the website. Paraphrase to avoid plagiarism).
a) What is the point of view of the diagram of “The Tree of Life” on this website?
b) How is the diversity of bacteria distorted in this diagram?
c) What’s been left out of this diagram?
d) The common ancestor of all life was between which two major branches of the evolutionary tree.
4) Watch the “Evogeneao Tree of Life Introductory Video “(https://www.evogeneao.com/explore/videos). It’s about five minutes. You are unlikely to understand how to complete the assignment unless you take the time to watch it.
5) Click on the image of the “”Tree of Life” at the top of the page. I recommend saving it and printing it out in landscape mode. You can also expand the image using the key presses assigned to do that on your system.
Use the diagram to answer the following questions:
a) Approximately how many years ago did life first evolve?
b) Approximately when did the common ancestor of plant and animals branch off from the bacteria?
c) Approximately when did the armored fishes go extinct?
d) When did most of the dinosaurs go extinct?
e) Which branch of the dinosaur tree is extant (still alive today)?
f) Name three groups that first appeared during the “Cambrian Explosion”. This was a period of time when there was a rapid diversification in life.
6) Go to the “Explore” menu and choose “Tree of Life Explorer”. The video you just watched gave instructions on how to use the explorer. Basically you click on the group's name that you want to trace ancestry to with humans. Hit the reset button before doing the query.
7) a) What degree of cousin’s and how many times removed are frogs from Humans?
b) Approximately how long ago did we share a common ancestor with frogs?
c) What degree of great grandparents is the common ancestor of frogs and humans? Yes, you had a great grandparent that was also the great grandparent of frogs.
8) Please answer the same three questions as in question 7, by tracing the ancestry of humans and bacteria.
9) Choose any two groups of organisms and answer the same three questions as in question 7, by tracing your common ancestry with them.
6/1/18
1
How many species?
Described vs Predicted
Described Species
1.6 million
Which groups have the most described species?
Which have the most
predicted number of species?
6/1/18
2
Described Species
1.6 million
Vertebrates – 46,000, 2.9%
Described Species
1.6 million
Arthropods – 955,000, 62%
Described Species
1.6 million
Plants – 230,000, 15%
Predicted Number
5 million to 150 million
6/1/18
3
Mollusks
6/1/18
4
Protozoa
Crustaceans
6/1/18
5
Plants
Arachnids
6/1/18
6
Roundworms
Fungi
6/1/18
7
Bacteria and Archeabacteria
Algae
6/1/18
8
I n s e c t s
Why the disparity between described and predicted
numbers of species?
Why do some groups have so many undescribed species?
• Small organisms harder to find. • Small organisms have a greater number of
potential ecological roles. • They are in older groups – longer period of
time for more species to evolve. • Fewer taxonomists working on them
describing species. • Less funding to support work on some
groups.
,
Patterns of Species Diversity I
Species
• Variation in life’s form is not continuous.
Species
• Variation in life’s form is not continuous. • Life comes in discrete packages.
Species
• Variation in life’s form is not continuous. • Life comes in discrete packages. • These distinct entities are species.
Species
• Variation in life’s form is not continuous. • Life comes in discrete packages. • these distinct entities are species • Objectively real; not artificial constructs.
Species
• Evolution not only produces changes over time within a lineage, but also creates new lineages.
Change within lineage
Creation of new lineage
Species
• Evolution must produce not only changes over time within a lineage, but must also create new lineages.
• What mechanisms create and maintain new species?
What is a species?
• Not fully addressed until 1930s — Dobzhansky, Mayr.
What is a species?
• Not fully addressed until 1930s — Dobzhansky, Mayr.
• Thought of species as reproductive communities.
The Biological Species Concept
• “Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups.”
Taxonomy Science of classifying organisms.
Ocelot
Bobcat
Margay
Jaguar
Taxonomic Classification
Nested Hierarchy
Taxonomic Categories Taxonomic Designations
Taxonomic Classification of Leopard
Panthera pardus (binomial nomenclature)
Panthera
Big Cats
can Roar.
Leopards
Leopards
Felidae Retractable
Claws
Leopards
Carnivora Carnassial teeth
Leopards
Mammalia Mammary
glands Hair
Chordata Notochord
Dorsal Nerve
Leopards
Leopards
Animalia
Leopards
Eukarya
What about groups of mammals?
How are they related?
27
Systematics Science of determining evolutionary relationships
among organisms.
Shared derived characteristics
Synapomorphies
Carnassial teeth
Retractable claws
Musk glands
Long legs, lithe bodies
Defensive Musk Gland
,
Patterns of Species Diversity II
Archaebacteria
Archaebacteria
• Mostly anaerobic (no oxygen). • Different genetic structure. • Different chemical in cell walls. • Fats have different structure. • Live in extreme environments. • No nucleus – DNA in long strands. • No organelles.
Eubacteria
Eubacteria
• Diverse ecologically. • Typical RNA of most life. • Evolved about 3.5 billion years ago. • No nucleus – DNA in long strands. • No organelles.
Eukaryotes
Eukaryotes
• DNA organized as chromosomes. • Chromosomes in nucleus.
Eukaryotes
• DNA organized as chromosomes. • Chromosomes in nucleus. • Have organelles.
Mitochondria
The Evolution of Mitochondria
The Endosymbiotic Theory
Lynn Margulis UMASS –
Geosciences
The Origin of Mitosing
Eukaryotic Cells 1966
Endosymbiotic Theory
• Mitochondria and Bacteria – Same form of DNA.
Mitochondria
Endosymbiotic Theory
• Mitochondria and Bacteria – Same form of DNA. – Same type of Ribosomes.
Mitochondria
Endosymbiotic Theory
• Mitochondria and Bacteria – Same form of DNA. – Same type of Ribosomes. – Both reproduce by binary fission.
Endosymbiotic Theory
• Mitochondria and Bacteria – Same form of DNA. – Same type of Ribosomes. – Both reproduce by binary fission. – Same size.
Endosymbiotic Theory
• Mitochondria and Bacteria – Same form of DNA. – Same type of Ribosomes. – Both reproduce by binary fission. – Same size.
• Animals inherit mitochondria from mother.
Eukaryotes
• DNA organized as chromosomes. • Chromosomes in nucleus. • Have organelles. • Evolved about 1.5 billion years ago.
Eukaryotes
• DNA organized as chromosomes. • Chromosomes in nucleus. • Have organelles. • Evolved about 1.5 billion years ago. • Larger then bacteria.
Eukaryotes
• DNA organized as chromosomes. • Chromosomes in nucleus. • Have organelles. • Evolved about 1.5 billion years ago. • Larger then bacteria. • Everything except bacteria made up of cells like these.
Protists
Protists
• Eukaryotic cells. • Anything not an animal, plant or fungi. • Most unicellular. • Single cells carries out all the specialized function that in other eukaryotes done by collections of cells.
• Most live in water or damp environments.
Plants
Plants
• Eukaryotic cells. • Multicellular. • Photosynthetic – Autotrophic.
Chloroplast
Plants
• Eukaryotic cells. • Multicellular. • Photosynthetic – Autotrophic. • Develop from embryos.
Plant Embryo
Fungi
Fungi
• Eukaryotic cells. • Multicellular. • Spore reproducing. • Form hyphae (fine tubes). • Hyphae may form masses of mycelia.
Fungi
• Eukaryotic cells. • Multicellular. • Spore reproducing. • Form hyphae (fine tubes). • Hyphae may form masses of mycelia. • Some symbiotic with algae and form lichens.
Animals
Animals
• Eukaryotic cells. • Multicellular.
Multicellular
Animals
• Eukaryotic cells. • Multicellular. • Develop from haploid egg and sperm.
Animals
• Eukaryotic cells. • Multicellular. • Develop from haploid egg and sperm. • Heterotrophs – energy from outside of cell.
Animals
• Eukaryotic cells. • Multicellular. • Develop from haploid egg and sperm. • Heterotrophs – energy from outside of cell. • Radial or bilateral symmetry.
Two types of symmetry
Radial symmetry
Bilateral symmetry
