Flashcards in 5. Further Evidence for Evolution Deck (21):
What are domesticated animals (animals reared for human use) related to?
- your mum
- wild species
- in many cases, the domestic and wild animals can still interbreed*
*NB: If the two populations (domesticated and wild) could interbreed, the 'wild species' answer would change to 'wild population'.
How have domesticated breeds been developed?
domesticated developed from wild species:
- selecting individuals with desirable traits, and breeding them
Define selective breeding.
selecting individuals with desirable traits, and breeding them
How does selective breeding contribute (as a piece of evidence) to the theory of evolution?
striking differences between heritable characteristics of domesticated breeds = evidence that species evolve
What else, apart from selective breeding, has given us strong evidence for evolution?
research into fossils
Give some examples of organisms that have been found as fossils.
trilobites and dinosaurs
Can any organisms alive today be found as fossils?
What does the fossil record suggest?
that organisms change over time
- we have found fossils
- they are very old, no fossils have been found of organisms that are alive today
- this shows that organisms change over time (as the theory of evolution states)
What does dating rocks allow us to do?
we can deduce the age of the fossils that lived in the rock
from that we can deduce when they lived on the earth
What does the sequence in which organisms appear in the fossil record match?
the sequence with which organisms appear in the fossil record matches their complexity, going from less to more complex as the fossils get closer to the present day
What appears in the fossil record first? Then? When do land vertebrates begin to appear in the fossil record?
- bacteria and simple algae
- fungi and worms
- recently (relative to bacteria)
So what can we deduce about a particular organism from the fossil record?
their likely ancestors
Give an example of a fossil that has similarities to present day vertebrates.
Give similarities and differences of the Acanthostega to modern day vertebrates?
- four legs like most amphibians, reptiles and mammals
- eight fingers, seven toes (no organism today has this)
- legs + fish like tail + gills = lived in water
What does the Acanthostega example show?
that land vertebrates could have evolved from fish via an aquatic animal with legs
What are dark varieties of light coloured insects called?
What is the most famous example of melanism as evidence for evolution?
Biston betularia (peppered moth)
Which variety of the Biston betularia was rare in England pre 19th Century?
the melanistic variety was rare, the peppered variety was common
What happened to the speckled variety of the peppered moth in industrial areas?
became much less common, the melanistic variety became more common
Why is the Biston betularia example evidence of evolution?
change in heritable characteristic (appearance of wings changing colour from speckled dark bits to fully dark) is an example of evolution