Showing posts with label migration. Show all posts
Showing posts with label migration. Show all posts

Wednesday, 11 May 2016

Migration

Migration

 As I have said in my earlier posts humans first evolved in Africa, according to the national Geographic the first homo sapiens fossils were found in Omo Kibish in Ethiopia, they are dated from around 200,000 years ago. In my earlier post I briefly mentioned when we moved to each continent. This time I will be going into it in greater detail.

 Haplogroups. These are the different DNA groups found across the world. Each major group is given a different letter of the alphabet and the sub groups have their own unique code. From what I could find there are groups ranging from A-T. The difference in the DNA of people in one haplogroup to another is only slightly different, the changes came about due to mutations and the adaptions homo sapiens made on their travels while being exposed to new conditions and surroundings. We could say that these different DNA groups separate people into "breeds" it could be controversial but I am only going to use it to keep things simple. These haplogroups can be used to identify where your "breed" first came about and where they traveled to. This can be done by taking a DNA test, get your DNA categorized into a haplogroup and then find out where fossils with your haplogroup were found. There are loads of maps online showing you where these haplogroups created routes across the world. The National Geographic have a basic but good interactive map showing you some of these routes, I will post a link in the comments.

 The most common haplogroup in Ireland is R1b, it supposed to have first arrived in Europe 40,000-30,000 from West Asia during a warm period. There is much debate over where and when haplogroups arrived and mutated. I read on another blog, which was all about genetics, about how the R1 group was split in two (roughly), R1a and R1b, during the ice age after the R1 group landed in Europe but in the comments some one was saying that, that was not how it happened. The person in the comments said the R1a and R1b groups came to Europe separately with R1a coming from the area near India and R1b coming from Western Asia. That is just one example of a difference of opinion or people getting the wrong facts, I personally do not know which one is true, it is very hard to find reliable information on this topic. This is due to the relatively short time scientists have been studying this for.

 What caused homo sapiens to migrate? Well a lot of events have occurred over time which are very relevant to geography, there were the ice ages, extremely cold times where humans avoided as best they could, the opposite with droughts and famines causing people to move in search of water or food for survival, when a hunter gather's spot became depleted, then there is the basic human instinct of curiosity and linked to ourselves we have war and greed, some haplogroups or civilizations attacking others for land, food and wealth. Not only did the geography have an effect on where and how humans lived but we also had a hand in changing the geography of the earth. You'll have to wait for the next post though for that.

Thursday, 5 May 2016

Where do we come from?

Where Do We Come From?

  Some scientists believe we humans started off in Africa, that is where we evolved. The proof is from the fossils of the earliest humans who lived 6-2 million years ago are all entirely from Africa. There is much debate over how we evolved from other humanoid species and which ones were actually human and others that were just apes, they agree that they are all primates. There are many factors taken into consideration to define whether a fossil is human or not. Some of these are; if the species was bipedal, in other words can they walk, how large the brain was and its capacity to do things such as, use tools, communicate using language and complex symbols or gestures, and if the species lived in communities and had a sense of culture.

 Evolutionists believe that early humans first evolved in Africa, as I said earlier, then they travelled to Asia between 2 and 1.8 million years ago, we first arrived in Europe around the time between 1.5 and 1 million years ago. As the years went by different species populated more and more areas of the planet, with us arriving in Australia 60,000 years ago and arriving in the Americas within 30,000 years ago.

 Then there is the other side of the debate with different religions and beliefs arguing that there is a maker or creator. A lot of these religions and beliefs did originate in Africa and Asia which is where our earliest human fossils are found

 Here is a list of major steps in human evolution in order of when they occurred, according to the website of the Smithsonian National Museum of Natural History; from around 6 million years ago there is evidence of the first bipedal species; the Sahelanthropus, but this was not their main way of travelling they still did a lot of climbing. With 2 million years passing these early humans were now mostly walking on two legs but they were still good climbers, allowing them to have the best of both worlds. To this day the use of tools is one of homo sapiens greatest assets, this started close 2.6 million years ago. Another one of our greatest assets and achievements is the discovering and controlling of fire, which improved the way we live ever since, with the use and cooking, smelting, cleaning, a forming of community, protection from predators and warmth. From the time fire was discovered which was around 800,000, the brains of many species started to increase in size, this was due to the need for a more complex brain for our survival. Farming began around 12,000 years ago when humans discovered they could plant and replant many plants and they could also breed and control many different animals.This led to the settling of people and then the start of civilizations.