Final Term Exam Flashcards
Useless remnants of structures or organs which were prominent and functional in ancestors
Vestigial Organs
or
Rudimentary Organs
The 10 vestigial organs in man
- vermiform appendix
- auricular muscles of external ear
- nictitating membrane
- palmaris longus
- vestigial tail vertebrae
- lobe of external ear
- wisdom teeth
- canines
- mammary glands in males
- body hair
The reappearance of ancestral characteristics in an organism which do not normally occur
Atavism
or
Reversion
The 6 examples of atavism
- cervical fistula in man
- tail
- mammary glands
- hair on body and face of Irish Dogman
- disappearance of phalanges of 2nd and 4th digits of horses
- homodont dentition in piscivorous cetaceans
The 3 types of atavism
- Family Atavism
- Race Atavism
- Atavism of Teratology
Type of Atavism
Sudden reappearance of a character after remaining latent for several generations
Family Atavism
Type of Atavism
Appearance of a character present in one race but not in another
Race Atavism
Type of Atavism
Appearance of abnormal characters in one race which are normal in another
Atavism of Teratology
States that living organisms do not exhibit evolutionary irreversibility
Dollo’s Law
It means an individual during its development repeats the most important changes which its ancestors have undergone during the long course of their evolution
Ontogeny recapitulates phylogeny
- Ernst Haeckel
- Recapitulation Theory
The 7 levels showing Haeckel’s Recapitulation Theory
- Similarities in early embryonic development
- Resemblance in vertebrate embryos
- Resemblance in invertebrate larvae
- Temporary embryonic structures
- Development of vertebrate organs
- Retrogressive metamorphosis
- Recapitulation Theory and Biogenic Law
The 4 homologous structures in vertebrate embryos
- similar head with rudiments of eyes and ears
- pharyngeal clefts or gill clefts, notochord, and embryonic tail
- limbs which develop as limb buds
- notochord replaced by vertebral column
The presence of […] in annelids and mollusks indicates their origin from the same ancestor
trochophore larva
The similarity in the […] larva of Echinodermata and […] larva of Hemichordata suggests common ancestry
- bipinnaria
- tornaria
The 3 temporary embryonic structures
- visceral pouch or gill cleft
- notochord
- tooth buds
The degenerative changes wherein an active larva transforms into a sedentary adult
Retrogressive Metamorphosis
Occurs when the larva fails to undergo metamorphosis; however, it develops gonads, attains sexual maturity, and starts reproduction
Neoteny
or
Paedogenesis
(Ambystoma mexicanum)
The Recapitulation Theory was first proposed by […] and eventually revised and renamed […] by Ernst Haeckel
- Von Baer
- Biogenetic Law
[…] provide the most direct evidence of evolution, whereas all other evidences are indirect
Fossil records
The 6 types of fossils
- unaltered remains of entire organisms
- petrified fossils
- molds and casts
- prints or impressions
- tracks and trails
- coprolites
The study of distribution of animals and plants on Earth in space and time
Biogeography
He divided the Earth surface into 6 biogeographical regions called realms based on the distribution of birds
Philip Lutley Sclater
The 6 realms (Sclater)
- Nearctic
- Palearctic
- Neotropical
- Oriental
- Ethiopian
- Australian
The 5 bases of evolutionary relationships from geographical distribution
- biogeographical division of the Earth
- diversity in fauna and flora
- discontinuous distribution of closely related species
- restricted distribution
- life on oceanic islands
Organisms which exhibit characteristics of more than one group
Connecting Links
The connecting link between nonliving and living organisms
Viruses
The 4 nonliving characters of viruses
- can by crystallized like inorganic and organic compounds
- devoid of enzyme systems
- unable to respond to external stimuli
- do not grow in size
The 3 living characters of viruses
- multiple inside a living host
- undergo mutations
- possess property of recombination and heritability
A protozoan said to be a connecting link between plants and animals
Euglena