Transcript The Story of Human Evolution

The Story of Human Evolution
Part 1: From ape-like ancestors to modern
humans
Part 2: What makes us human? Evolution and
adaptation in modern humans
We are all close relatives in our DNA
Modern humans continued to evolve as
they encountered new environments, new
diseases and new ways of living
Evolution is a gradual change in genetic
makeup from one generation to the next
Evolution can happen by chance, or by
natural selection
How natural selection works
1. Individuals are variable
How natural selection works
1. Individuals are variable
2. Some variations are inherited
How natural selection works
1. Individuals are variable
2. Some variations are inherited
3. Individuals with the most favourable
variations have more offspring
Favourable variations become more common
Over time, natural selection changes
organisms in response to their environment
Evolution in action: Lactose tolerance
Domestication of cattle drove selection for
lactose tolerance
Percentage of people with lactose intolerance around the world
Evolution in action: Blue eyes
Blue eyes result from a single genetic change
less than 10,000 years ago
Blue eyes are not physically advantageous, but
may have been more attractive
Percentage of Europeans
with light-coloured eyes
Are we still evolving?
?
Modern life has
changed but not
stopped human
evolution
The invention of agriculture and associated
dietary and lifestyle changes still drive human
evolution today
Gene variants involved in dietary changes and
disease resistance are continuing to evolve
Disease is an important driver of evolution
Malaria is one of the world’s most
prevalent and fatal diseases
Genes that confer resistance to malaria
are strongly selected for
Malaria resistance genes are at high
frequency in Africa
Allele frequencies of malaria resistance gene FY*O
P C Sabeti et al. Science 2006;312:1614-1620
The future of human evolution
© Produced by Hilary Miller in association
with the Allan Wilson Centre for Molecular
Ecology and Evolution
Thanks to Azra Moeed, Caroline Thomas, and
Glenda Lewis for assistance with preparing
this presentation
[email protected]
http://www.allanwilsoncentre.ac.nz
Image credits
Slides 1, 2: TRANZ INTERNATIONAL Image Library Ltd
Slide 3: TRANZ INTERNATIONAL Image Library Ltd and iStockphoto
Slide 4: Science Photo Library
Slide 5: Wikimedia Commons
Slides 6-8: Univ. of California Museum of Paleontology (http://evolution.berkeley.edu)
Slide 9: Moth - Sarah Beach, stock xchng; Gecko - TRANZ INTERNATIONAL Image Library Ltd;
Kakapo – Wikimedia Commons
Slide 10: Wikimedia Commons
Slide 11: Igor Spanholi, stock.xchng
Slide 12: Wikimedia Commons
Slides 13, 14: TRANZ INTERNATIONAL Image Library Ltd
Slide 15: Wikimedia Commons
Slide 16: Science Photo Library
Slide 17: TRANZ INTERNATIONAL Image Library Ltd
Slide 18: Fields – Eva Schuster, stock xchng; Barley – David Thomson, stock xchng; Crowd - TRANZ
INTERNATIONAL Image Library Ltd
Slide 19, 21: TRANZ INTERNATIONAL Image Library Ltd
Slide 22: Science Magazine, American Association for the Advancement of Science
Slides 23-25: TRANZ INTERNATIONAL Image Library Ltd