Kingdoms Beginnings of Evolution Taxonomy & Diversity Origins of Diversity Phylogeny/ & Human Evolution 100 100 100 100 100 200 200 200 200 200 300 300 300 300 300 400 400 400 400 400 500 500 500 500 500
There are six kingdoms Bacteria Lack a nucleus and grow in a variety of environments Archea Live in extreme environments Protists A diverse group of organisms, comprising those eukaryotes that cannot be classified in any of the other kingdoms as fungi, animals, or plants. Fungi Obtain food by absorbing nutrients. They do not photosynthesize. Plants Non motile and obtain food through photosynthesis. Animals Motile and ingest food they have obtained.
What was Aristotle’s original classification of Kingdoms? Why did it not work?
Plantae and Animalia • Does not always fit – sponges and corals fixed in one place however they do not make their own food through photosynthesis
Carbon and energy sources for organisms in this Kingdom consist of 4 major classifications:Photoautotrophs Photoheterotrophs Chemoautotrophs Chemoheterotrophs
Explain the lytic cycle. What type of organism would go through the lytic cycle?
Fungi can reproduce sexually or asexually. Explain how and why this works.
An interesting fact is that depending on the environment the mold is living in, that will determine what type of reproduction will be utilized: sexual or asexual.
Both related to Genetic DriftFounder - few individuals create a new, isolated population so alleles that they bring have extreme importanceex. Amish and Ellis-van CreveldsyndromeBottleneck - dramatic, often temporary, reduction in population size, usually resulting in significant genetic drift
A sample of igneous rock is found to contain the radioactive parent and daughter isotopes of uranium, 235U and lead, 207Pb, in the ratio of 12.5%:87.5%. Assuming that no 207Pb was present when the rock was first formed; estimate the age of the sample. The half life of 235U is 713 million years.
Certain different characteristics found between two populations in response to their environment may allow new species to develop
Select one of the following scientists and indicate their theory of species development. Lamarck, Lyell, Cuvier, Buffon
Bacterial ResistanceBacteria exposed to antibiotics will eventually develop new strains that will be resistant to the antibioticsConjugation through pili
Who was the first scientist to use a system by which to classify organisms based on what they looked like Latin and Greek stems were used to facilitate the process
Carolus Linnaeus – circa 1750Used physical characteristics to classify organisms into groupsLatin and Greek stems (Felis domesticus)Names given often reflect characteristics of organism or to honour a scientist or historical figure
State one of the types of Selection that can occur and explain it. Think hummingbirds.
Stabilizing selection – selection against individuals with traits that deviate from the population average • Directional selection – selection that favours an increase or decrease in the value of a trait from the current population average • Disruptive selection – favours individuals at opposite extremes of a trait over individuals with intermediate variations • Sexual selection – favours the selection of any trait that influences the mating success of the individual
If species from different populations ever migrate back to each other hybridization may or may not occur depending on isolating mechanisms. What are the names of these mechanisms and how do they differ?
Prezygotic Isolating Mechanisms prevent formation of zygotes and includes geographical, ecological, temporal, behavioral and mechanical isolation. Postzygotic Isolating Mechanisms prevent proper functioning of zygotes and therefore development to maturity and therein ability to reproduce.
Changes in characteristics are produced by two items. What are they?
Random genetic mutationsIntroduce varietyEspecially important in asexual organisms2. Selection for a particular characteristic that increases the organisms chance of survival and breeding in a particular environment
Larval and adult forms of organisms can be very different and they are the same species!
Comparisons based on proteins and hormones that comprise organisms is known as comparisons made based on _________________.
Human arm, horse’s leg, bat’s wing and whale’s flipperAll specialized for what they do but they have the same evolutionary origin - homologous
How are DNA comparisons between humans and other organisms (species) completed?
Human single strands of DNA are compared to other organisms and the amount of complementary base pairing that occurs indicates relatedness
Mitochondrial DNA can also help to determine how long ago species began to diverge from a common ancestor How does this work?
It mutates at a predictable rate so it provides a molecular clock for measuring rates of evolution. Mitochondrial DNA – mother to offspring
Hypothesis about the evolutionary history of groups of organismsCommon ancestors share characteristics of all organisms that come after in a phylogenetic treeSmaller differences help to distinguish genus’ from each other
Based on fossil evidencehow long ago is it believed that each of the following developed?Prokaryotic cells?Eukaryotic cells?Multicellular organisms?
Fossil evidence • Prokaryotic cells – 3.5 billion years ago • Eukaryotic cells – 1.5 billion years ago • Multicellular organisms – 700 million years ago
Explain how the multiregional hypothesis differs from the monogenesis hypothesis.
Multiregional Hypothesis anatomically modern humans evolved in parallel in a number of places (Africa, Europe, Asia). Gene flow accounts for them not becoming distinct species.Regional genetic diversity arose due to regional selective pressures over about 1 million years.Monogenesis HypothesisH. sapiens evolved only in Africa and then migrated displacing Neanderthal and other H. erectus populations.Regional genetic diversity arose in humans with the past 80 000 to 100 000 years, that is, since H. sapiens left Africa.
phylogentictree? Select 3 species from this cladogram and state one fact about each.
Australopithecines 6 different species between 4.2 and 1.0 million years ago. Generally a group of extinct hominids closely related to humans.Homogenus Africa, 2.4-1.6 million years agoH. habilisH. erectus about 1.6 million years ago. H. erectus used stone tools and fire. Brain size around 750cm3 (1200cm3 today), a rounded head and smaller teeth…more like current human features. H. erectus moved out of Africa into Asia and Europe.H. erectusH. neanderthalensis and H. sapiens about 600 000 years ago.H. sapiens first appeared in Africa 130 000 years ago and H. neanderthalensis was already living in Europe and Asia
What is the endosymbiotic theory in terms of development of eukaryotic cells?