Evolution Flashcards
Natural selection
The process where organisms better suited and adapted to their environment survive and reproduce more offspring, passing on traits
Four feature living systems
Evolution:
The gradual orderly change in the events of the universe, including living and non living things. It means ‘unfolding’ or ‘unrolling’
What are the evidence for evolution x6
- fossil record
- bio geographical
- comparative embryology
- molecular/ bio chemical
- observable evolution
- comparative anatomy
Coprolite:
Fossilised feces
What does coprolite tell us?
- diet
- size of animal
- environment
Vestigial organs:
An organ or part of anatomy that was once useful in the past but has lost its original function over time
Natural selection question
- population at start
- what happens to one population
- variation
- what happened to other population
- survived, reproduced and traits were passed on to offspring
- specific species increased
Foramem Magnum:
The hole in the base/rear of skull through which the spinal cord passes
Brow ridge:
Bony ridge located above the eyes
Palaeontology:
Scientific study of prehistoric life. It studies fossil organisms and related remains
Cranium:
Part of skull that encloses the brain
AKA brain case
Artificial selection:
It is intensional breeding for certain traits
Biogeography:
Uses present day geographic distribution of an organism and the fossil record to show the distribution of a species in the past, compared with its distribution today
Bipedal:
Locomotion using two legs for walking
Genus:
A group marked by common characteristics
What are selective pressures?
- biotic factors
- abiotic factors
Biotic factors:
- predators
- disease
- competitors
- prey
- mating partners
Comparative embryology
Shows that some organisms have a common origin based on similarities in embryonic form
Burial of sediments means
No disturbance/ scavengers/ wind/ water
Reduces available oxygen that would usually decay organisms
Embryology
Study of embryos and their development
Molecular biology
Genetic similarities
Comparative anatomy
Looks at similar (homologous) structures present in organisms suggesting common ancestor.
Abiotic factors:
- temperature
- shelter
- sunlight
- water
- nutrients
Who proposed the theory of natural selection?
Charles Darwin
Where are most fossils found?
In rock layers which were originally formed under water
What are 4 basic characteristics that result in natural selection?
- variation
- inheritance
- selection
- time
DNA hybridisation
Similarity of genetic material between different species, illustrating evolutionary relationship between species
What are the 3 stages of human evolution?
- big brain theory 1470
- Lucy walked on two legs
- flat face man
Pre requisites for a successful fossilisation to occur
- rapid burial
- hard parts
- must not be disturbed
Fossil:
Preserved remains of dead organisms
Different types of fossils
- mummified
- body
- trace (coprolite)
- Impression (casts, molds and carbon prints)
- petrification
- amber
- ice
Transition fossils:
Intermediate
What can fossils tell us about past?
- ancient disasters e.g. Volcanic eruptions
- habitat and condition organism lived in
- teeth can tell us diet
- bones can tell us how it moved
Observed evolutionary change
Antibiotics
Pesticide resistance
Where does variation come from?
Variation comes from a mutation which is a random change in a gene
What advantage is there in having both eyes facing towards the front?
- great judgement of distance
- x ray perception of depth
What disadvantage is there in having both eyes facing towards the front?
-lack panoramic vision more likely to being attacked
Ways that palaeontologist work out the age of fossils
- relative age based on stratigraphy
- indicator fossils
- use of radioisotopes
How might a biologist determine if a fossil skull came from a young animal or an adult?
- cranium size
- teeth or lack of teeth (wisdom teeth)
Lamarks theory:
Useful changes which occur in an organism during its lifetime will be inherited by its offspring
Neanderthal:
An extinct sub species of homo sapiens
Existed in Europe 600 000 to 350 000 years ago
Evidence of interbreeding between Neanderthals and early modern humans
- fossil evidence
- DNA evidence (1 to 4 percent of humans genetics made up of Neanderthals)
Relative dating
Placement in the strata (layers of the earth) of the planet
Using rock layers (stratigraphic correlation)
Neanderthal tools
- cutting tools
- spear points
- hand axes
Why did Neanderthals have large noses?
- to keep them warm
- adapted to cold winter
Adaption
Structure of bodily processor behaviour of an organism that makes it better suited to its environment. E.g. Ducks have weeded feet that propel them through water
Last Neanderthals lived in….
Europe and parts of western and Central Asia
Era
Period
Epoch
Cenozoic
Quaternary
Holocene
Two types of molecules that are used to determine the degree of relatedness between different species
- DNA and protein
- amino acids
Three ways fire was important to early humans
- cooking
- light
- warmth
- craft tools
Transition fossils:
- intermediate
- support evolutionary progression
- eg. Archaeopteryx
Homologous structures:
- suggest common ancestor and evolutionary relationship
- similar bone structure, different function
- divergent
- bats, horse, human
Analogous structure:
- look similar same function, different structure
- convergent/ parallel
Parallel evolution:
- related species evolve similar features independently
- eg. Eucalypts
Human skulls x8
- V shaped
- large brain case (1200cc)
- foramen magnum located at base
- no Sagittal crest or brow ridge
- flat face
- high forehead
- prominent lower chin
- snout doesn’t protrude
Gorilla skulls x8
U shaded Smaller brain case (400cc) Foramen magnum located at rear Sagittal crest and bony ridge Face sticks out Slopping forehead Receding chin Snout protrudes
The first human like creatures to walk upright are called
Australithecus
The hominid Lucy was a member of what group
A.afarensis
What is not part of Darwin’s theory
Traits acquired during an individuals life are passed on to its offspring
Relative dating
Australopithecus
An extinct genes of small brained, large toothed, bipedal hominids that lived in Africa between one and four Million years ago
Pentadactyl
Having five digits on each hand or foot
Paranthropus
A genus of extinct hominids also known as Robust Australopithecus. Bipedal hominids that descended from aumtralithecus but left no descendants
Homo
Genus of great ape that includes modern humans and species closely related to them
