Human Evolution
This topic centers on the main trends in human evolution.
The first trend is about the development of bipedalism.
The second trend is about brain and skull development.
The third trend is about cultural development and includes the migration and dispersal patterns.
The first trend is about the development of bipedalism.
The second trend is about brain and skull development.
The third trend is about cultural development and includes the migration and dispersal patterns.
Introduction and relationships
Primates:
Key features: Large brain relative to brain size, well developed binocular vision,grasping hands, nails not claws, sensitive hands, reduced smell.
Hominids: Hominins and the great apes. (Gorillas, Orangutan, Chimpanzees & Bonobos)
Hominins: Ancestral Homo sp including the Australopithecines
Some Bonobos
Key features: Large brain relative to brain size, well developed binocular vision,grasping hands, nails not claws, sensitive hands, reduced smell.
Hominids: Hominins and the great apes. (Gorillas, Orangutan, Chimpanzees & Bonobos)
Hominins: Ancestral Homo sp including the Australopithecines
Some Bonobos
Please search up for a video called: The Ape that took over the world: An excellent overview from the BBC. It is well worth a watch. I am unable to embed it here.
Image below is from pasttime.org
It gives you an overview of where we fit into the picture alongside the other primates . Their site is also quite good to visit and explore. It reads quite well and is relatively easy to understand
It gives you an overview of where we fit into the picture alongside the other primates . Their site is also quite good to visit and explore. It reads quite well and is relatively easy to understand
Bipedalism
Walking upright. This began to emerge round about 4.2 - 6 MYA in the Australopicthecines and following that in the Homo sp.
This development was probably the key development that fostered the subsequent evolution. It gave a huge selective advantage to these organisms, so much so that a wide variety of various Australopithecine and Homo sp. evolved.
This ability emerged very rapidly within possibly only about 2.5 MYA. (beginnings of bepedalism are dated at approx 5-6 MYA with Orrorin tugenensis.) pre-humans were fully bipedal by 4 MYA.
The main advantages included being able to carry things and also being able to keep cool. Being able to see further by standing upright allowed for better abilities to either avoid or attack predators. The use of carrying ability means that weapons in the form of sticks and stones could be thrown at predators. being taller meant that throwing ability would have been improved.
This development was probably the key development that fostered the subsequent evolution. It gave a huge selective advantage to these organisms, so much so that a wide variety of various Australopithecine and Homo sp. evolved.
This ability emerged very rapidly within possibly only about 2.5 MYA. (beginnings of bepedalism are dated at approx 5-6 MYA with Orrorin tugenensis.) pre-humans were fully bipedal by 4 MYA.
The main advantages included being able to carry things and also being able to keep cool. Being able to see further by standing upright allowed for better abilities to either avoid or attack predators. The use of carrying ability means that weapons in the form of sticks and stones could be thrown at predators. being taller meant that throwing ability would have been improved.
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Below is an excellent resource to use for this topic. It is from Cold Spring Harbor where our understanding of DNA took a giant step forward. This section focuses on Human evolution and is right up to date and in line with what you need to know.
Waikato University is one of the Universities which is actively preparing resources on this topic specifically for NZ Biology students. The link below will take you to their site and provide up to date information from the New Zealand perspective.
This Alpha publication below centres on the New Zealand view on human evolution
The PBS site is an interactive website where you can investigate human evolution.
The dispersal of our ancestors around the globe:Homo erectus was the first of the hominins to leave the African continent and disperse into the Middle East, Asia, Indonesia and Europe about 2 MYA. This migration was probably a result of climate change which had reduced food supplies. There are 2 theories describing the origins and dispersal of our species:
The Out of Africa theory is the most widely accepted. It is also known as the Recent Single Origin hypothesis. (Eve hypothesis) This theory is:
African San people are now thought to be the direct living link to ancestors of all people. (University of Pennsylvania, Dr Srah Tiskoff) The other theory is called the "Multiregional Theory" Main points:
San people
Understanding genetic markers. The y chromosome and mtDNA
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Using ToolsThe ability to use tools is very dependent on the ability of the hand to move and grip. This is called manipulative ability. Monkeys, apes and humans can all hold objects in a "power grip".
However, humans can use a "precision grip". This is because their thumb is able to meet the index finger and so is able to perform very fine movements such as holding a pen to write. Monkeys have too short a thumb to do this and their thumb does not rotate as well as a humans. Humans also have a muscle which allows the last joint of the thumb to bend. Monkeys do not have this muscle. In addition humans have a longer last bone of their fingers. 
Image below from http://www.odec.ca/
Below is a link to an excellent resource on tools with more detail from Palomar College in California:
Neanderthals: : Some 150,000 years ago Europe and Western Asia were dominated by an extraordinary race of human beings who were tall, around 6 feet or so, with an immensely strong physical build, and clearly intelligent, their brain was in fact slightly larger than that of modern man. They were called the Neanderthals. They had the strength and the courage and the social organisation to survive and thrive even through the terrible ordeal of the successive ice ages, which carpeted Northern Europe in perpetual snow and ice for years on end. They were the great survivors. Then suddenly, around 35,000 years ago they disappeared. Wiped off the map. Extinct. Replaced in some strange and inexplicable way by our own direct ancestors, Modern Man, homo sapiens, who went on to populate the entire world. The extraordinary disappearance of the Neandertals remains one of the greatest mysteries in the history of human evolution.
( to find out more, do a search, youtube have removed the clip) Published April 2013) The importance of language; This may have been absolutely the turning point in evolution of modern humans. The development of language depends on the ability to control breathing (Broca's area) and also then to understand the meaning of language (Wernicke's area)
The next is a pretty interesting 20 min Ted Talk from Mark Pagel on the importance and role of language evolution
Did we really share ancestral DNA with the other Primates? This is some proof and reasoning from ken Miller. 4 min clip extracted from a longer video
Find your place on our 'caveman-o-meter' by completing the seven evolutionary challenges.Each challenge allows you to move along the evolutionary scale from ape to man. (From the BBC.)
The development of thought and culture. From Nova science: Evolution: the Mind's Big Bang. https://www.youtube.com/watch?v=Ptz3lOmc1As You may need to search for this on youtube to watch it. (They disabled the link!) Below is a funny fast 3 minute simulation of the development of life on earth through to the future
Claudio Koob Finalist in 2014 Photographer of the Year
Facebook Update' by Marsel van Oosten Finalist in 2014 Photographer of the Year
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