Evolutionary and Functional Biology Lab Test

Natural Selection

Members of a population best adapted to their environment are more likely to survive and pass on their genes.

Evolution

Gradual change in inherited traits of a population over many generations

Variation (ENC)

Exists in all populations
Necessary for natural selection
Caused by mutations and sexual reproduction

Fitness

Ability of an organism to survive and reproduce in a particular environment

Phylogeny

Evolutionary history of a group of related organisms

Aim of phylogenic trees

show evolutionary histories through common ancestors

Cladistics

Depict hypotheses on how organisms are related based on shared traits

Clade

Group of organisms that includes ancestor species and all descendants. It is a relative concept depending on the species of interest.

Cladogram

Shows evolutionary relationships within clades

Sauropsids

Clade with birds and reptiles

Synapsids

Mammals and reptile-like ancestor

Linnean Classification

Classes are based on shared morphological traits.

Phylogenetics vs Linnaean Classification

Phylogenetics
-common ancestors
-time sequence
-organised in trees
-no language specificity

Linnaean
-hierarchal classification
-no time indication
-organised in taxons
-in latin

Comparative Morphology

Determining similarities in structures of related organisms

Embryology

Comparisation of embryo development across species

Terrestrial Embryos

Contain non-function gill slits in early fetal development

External Embryo

Hard shell protects the embryo

Internal Embryo

Contains fluid filled membranes

Molecular Systematics

Analysing molecular similarities of DNA, RNA and proteins.

Nearest living relatives for humans

Chimpanzees, Bonobos

Most vertebrates, except for ____ lose their gill slits by adulthood

Fish

Some vertebrates lose their tail. In ___ the tail is reduced to the tail bone.

Humans

Tiktaalik (fishapod)

Represents vertebrates exploring land

375 million year old fossil

Ichthyostega

Early animal capable of supporting its body in a terrestrial environment

363 million years ago

Fossil Development: Fish → Tiktaalic → Ichthyostega

No neck, no ribs, fins → neck, ribs → limbs

Transitional Fossils

Remains that exhibit traits common to an ancestral group and descendant group.