COMPA

• Similarities


  Corresponding parts may be considered similar in ancestry, function, and appearance
• Homology


  Similarity that reflects common descent and ancestry.
• Analogy


  Characteristics that serve similar functions
• Homoplasy


  Arrived at via independent evolution and features that simply look alike
• Serial Homology


  Similarity between successively repeated parts in the same organism
• SymmetryThe repetition of the parts in an animal or plant in an orderly fashion

  • SymmetryThe repetition of the parts in an animal or plant in an orderly fashionition of the parts in an animal or plant in an orderly fashion
• Radial Symmetry


  A body that is laid out equally from a central axis, so that any of several planes passing through the center divides the animal into equal or mirrored halves
• Bilateral Symmetry


  Only midsagittal plane divides the body into two mirrored images, left and right
• Asymmetry


  Having parts that do not match or that are not the same size, shape, or position
• Anatomical terms


  • Anterior - head end (cranial)
  • Posterior - tail (caudal)
  • Dorsal - back
  • Ventral - belly or front
  • Medial - midline of the body
  • Lateral - the sides
  • Distal - attached appendage to the body: farthest region
  • Proximal - attached appendage to the body: closest region
  • Transverse Plane - separates it into anterior and posterior portions
  • Superior & Inferior (in humans) - generally replace the terms anterior and posterior respectively
  • Pectoral Region - chest supports the forelimbs
  • Pelvic Region - hips supporting the hindlimbs
  • Frontal Plane (Coronal Plane) - divides a bilateral body into dorsal and ventral sections
  • Sagittal Plane - splits into left and right portions
• Segmented


  A body or structure built of repeating or duplicated sections (segment/metamere)
• Segmentation


  A process that divides a body into duplicated sections
• Invertebrate segmentation


  • Segmented tapeworm
• Craniates


  Chordates with neurocranium (braincase)
• Plesiomorphic


  • Primitive features
• Derived


  • Unique anatomical features
• Craniate 3 regional components

  • Head
  • Trunk
  • Tail
• Head


  • Special sense of organs
  • Large enough to receive, process and response to stimuli
  • Jaws for acquiring, retaining, and macerating food
• Trunk


  • Contains a cavity (coelom)
  • Body wall, surrounds the coelom
  • Neck, narrow extension of the trunk that lacks coelom
• Tail


  • Commences at the anus/vent (postanal)
  • Caudal continuation of body wall muscles, axial skeleton, nerves and blood vessels
• Craniates have 3 principal body axes

  • Longitudinal axis (anteroposterior)
  • Dorsoventral axis
  • Left and right axis
• Metamerism


  The serial repetition of structures in the longitudinal axis of the body
• Craniate Characteristics


  • Cranium - Bony, cartilaginous, or fibrous structure surrounding the brain, jaw, and facial bones
  • Three-part Brain - Brain are split in 3 regions devoted during the embryonic period: the forebrain, midbrain and hindbrain
  • Neural crest and its derivatives - Emerge from the dorsal edge of the neural tube during neurulation and then migrate extensively throughout the anterior-posterior body axis to generate numerous derivatives
  • Paired external sense organs
  • Cartilage - Strong, flexible connective tissue that protects joints and bones
• Vertebrate characteristics


  • Vertebral column - Provides attachments to muscles, supports the trunk, protects the spinal cord and nerve roots and serves as a site for hemopoiesis
  • Two semicircular canals - Maintenance of balance when the organism is in motion
  • Electroreception - Biological ability to perceive natural electrical stimuli
  • Lateral Line system - A distal touch reception system for detecting wave vibrations and currents in water; receptor cells (neuromast)
  • A number of additional soft tissue specializations
• Structure common to craniates

  • Notochord & vertebral column
  • Pharynx
  • Dorsal Hollow Central Nervous System
• Adaptation (biological)


  A hereditary modification of a phenotype that increases the probability of survival
• Preadaptation (protoadaptation)


  Traits have enabled a phenotype to meet new environmental challenges before it materializes
• Preadaptation


  • Lungs were present in many fishes long before they were called on to function on land
• Speciation


  Formation of new species preceded in almost every instance, if not in variability by geographical isolation of a population from other populations of the same species
• Isolation


  Organisms of the same species are separated, and this happens when there is something between the organisms that they can't cross
• Isolation


  • Petromyzon marinus dorsatus (freshwater) & Petromyzon marinus marinus (marine)
• Types of Speciation


  • Allopatric Speciation
  • Peripatic Speciation
  • Parapatric Speciation
  • Sympatric Speciation
• Allopatric Speciation


  • Northern Spotted Owl & Mexican Spotted Owl
• Peripatic Speciation


  • Southern Chestnut-tailed Antbird, Myrmeciza Hemimelaena & Northern Chestnut-tailed Antbird, Myrmeciza Castanea
• Parapatric Speciation


  • Bullock's oriole & Baltimore oriole
• Sympatric Speciation


  • Rhagoletis pomonella (apple maggot fly) Hawthorn & Apple
• Genetic Drift


  A mechanism of evolution characterized by random fluctuations in the frequency of a particular population (Bottleneck Effect)
• Evolutionary Convergence


  All of these animals have a streamlined body shape, adapted for life underwater
• Evolutionary Convergence


  • Shad (fish), Dolphin (mammal), Ichthyosaur (reptile), Puffin (bird)
• Ontogeny (ontogenesis)


  The developmental history of an organism