Whales Vestigial Structure

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Whales are one of the most common examples of organisms with vestigial structures. Vestigial structures are used as evidence of evolution because it shows a part of an organism that no longer has a function. Whales have hip bones remaining from the slow process of their legs decreasing in size. Factors such as swim speed and water temperature lead to the advantage of smaller legs.

Hans Thewissen, an Ingalls-Brown professor of anatomy, stated, "Studies on swimming in mammals show that a sleek body is necessary for efficient swimming, because projecting organs such as rudimentary hind limbs cause a lot of drag, and slow a swimmer down.” Whales with larger legs tended to be slower, resulting in difficulty catching fast prey. They have

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Outline: Species and Kingdom Animalia Essay

Kayla Dougherty 3/15/2012 Biology Half Sheet 1. Humans are classified like any other organism by their kingdom, phylum, class, order, family, genus, and species. Humans are in the kingdom Animalia. This is because we are heterotrophs and are multicellular. Humans are in the phylum Chordata. This is because we have a backbone. We belong in the class Mammalia because we give milk, have hair all over, and we give birth to offspring. We are in the order Primates because we have and opposable…

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Evolution: Evolution and Organisms Essay example

Homologous structures: structures that have different functions or appearances but had similar origins and are found in closely related species (like: arm – seal flipper – bat wing – dog forepaw)  Analogous structures: structures that have similar functions and appearances but came from different, evolutionarily unrelated organisms (like: bat wing – bird wing – butterfly wing).  Mutations (change to the genetic blueprint); genetic changes that result in changes in the organism.  Vestigial organs:…

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Essay on Cetacean

The order Cetacea includes the marine mammals known as dolphins, whales, and porpoises. The sub-orders include; Mysticeti, Odontoceti, and Archaeoceti. The Archaeoceti are ancient, extinct whales. Cetus is Latin and means "whale". its original meaning, "large sea animal", was too general. Some Cetacean species are highly intelligent and scientific movements have been made to classify them as "non-human persons." Cetology is the branch of marine science that deals with the study of cetaceans.…

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Human Population Bio Study Guide

adapted to life among their environment) b. Adaptation 4. Comparative Anatomy a. Homologous structures i. Similar Structure, Different Function. ** Means shared ancestry b. Analogous structures i. Different Structure, Similar Function ** Superficial similarity due to similar function ii. Independent selection c. Vestigial structures i. “Evolutionary Baggage” ii. Once needed at one point, now uneccesary iii. Ex: Whale – Pelvis, Femur; Humans – Coccyx, Ear muscles, Third Molar 5. Comparative Embryology a…

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Comparative Anatomy Provides Structural Evidence Of Evolution

of the relatedness of organisms. Structure, inexorably tied to function, also provides evidence of descent with modification. The elephant and the mammoth, for instance, clearly have similar anatomies and share a common ancestor. Unrelated Species in Similar Environments Have Evolved Similar Forms Evolution by natural selection also predicts that, given similar environmental demands, unrelated species might independently evolve superficially similar structures, a process called convergent evolution…

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Bio Notes Essay examples

lineage. a. Fossil record - different layers = different ages in past - Fossils show pattern of change consistent with geologic age b. Homologous structures and vestigial organs. *Descent with modification - Wings of birds/mammal forelimbs - Vertebrate skeletons - Bones in whale flippers, snake pelvis c. Biochemistry and Molecular Biology - unity of origin : same biomolecules and metabolism in all organisms - closely related organisms…

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BIOLOGY GRADE 11 NOTES Essay

Seed cracker finch  Can lead to speciation Directional selection  Occurs when selection favours one particular variation  Ex. Peppered moth Sexual Selection  Selects for an organism’s ability to obtain a mate and reproduce  Can create structures and behaviours that are harmful to an individuals’ survival  Ex. Peacock tail: attracts females but predators too  Intrasexual Competition with one sex: attention of females,…

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