Whilst it is true that perhaps, Darwin did not explain the origin of life, it has since been able to be worked out. I'm not claiming absolute knowledge on this matter, but this is what I believe:
-newly formed earth (a few hundred million years old) is abundant with water and nutrients from asteroid impacts (although some nutrients are toxic)
-CO2 layer and other gases in atmosphere start to warm planet
-first protein is formed (it is important to realise that this is NOT life yet, only a very complex molecule)
-more proteins are formed, as well as more complex molecules such as glucose.
-cell-like structures which can convert CO2 to O2 whilst creating glucose slowly form from the mixture of molecules. (scientists believe that these were very primitive algae)
-sufficient O2 in atmosphere after a few million years of photosynthesising, bacteria start to form in nutrient rich seas.
-some bacteria photosynthesise like the algae, some start to use the O2 to create glucose and release CO2, start of the carbon cycle.
-eventually unicellular organisms move closer to shore (due to overcrowding near the middle of oceans) where they are exposed to greater levels of O2.
-more O2 is more beneficial, so primitive gills start to form
-organisms now able to produce more glucose as gills are more efficient, excess energy, first multicellular organisms
-first primitive sea creatures are formed.
-eventually larger and larger organisms are mutating out of the others as there are more efficient ways to process the nutrients in the water, son more energy available for growth
-by now, some of the 'algae' have moved onto damp land around the seas and early plants and trees start to form.
-organisms that fed on algae have to adapt to gain algae from other places than the sea. At first, they start to jump quickly out of water and grab what they can, of course not every attempt successful.
-eventually primitive legs on fish start to form limbs (see:
http://en.wikipedia.org/wiki/Tiktaalik )
-organisms spending more and more time above sea level due to 'legs'
-primitive lungs formed
-some species move onto land
-scales adapt to become skin like on reptiles, some become wing-like structures, (which go on to form feather like structures and eventually birds
-some move further inland, where they either start to eat other vegetation or become carnivores
-some move into jungle areas, start swinging from trees and climbing up then to get food (early primates)
-similar ancestors to the primates move to less jungle areas and begin to stand on hind two legs in order to run faster and catch prey better
-these begin evolving into modern day homosapien sapiens, who have larger brains and are capable of self recognition and intelligent thought
Now I can't stress enough that there was a long time between the next step (millions of years).
I'm also sure that what I have written is not 100% complete or in detail as it should be (that's what books on this subject are for)
As for the termites: they are two species which benefit from the work of one. The termite CAN digest some of the nutrients by itself, just not all (i.e. cellulose). The cellulose is broken down by another organism which can do it, and the energy is used by both. And by the way you have organisms living inside you. Billions of them, in fact, more than what you have as body cells. In your gut, the bacteria help to: Stimulate the production of antibodies in your blood, increasing your immune system strength and capacity to deal with toxins, allergens, harmful microorganisms, and incompletely digested protein
Produce nutrients that are essential to your health like Vitamin B12 and Vitamin K
Take up space and resources in your gut, which helps to prevent infection by harmful bacteria, fungi, and parasites
Produce natural antibiotics, acids, and hydrogen peroxide, which also help to protect you against infection by harmful microorganisms, including bacteria that can cause food poisoning
Help to digest food
(drbenkim.com)
Ossie
]My name is Ossie, I'm from London and I'm 16. I consider myself a believer in evolution and an Atheist. Please don't be put off by this, I do not think any less of those who don't believe in this, as even if there is a God or not, humans are intelligent beings that are able to make their own independent decisions.
