- 1- how did other animals such as snakes evolve and
their venom got created?
Snakes evolved from lizards. http://en.wikipedia.org/wiki/Snake#Evolu… Early snakes started out with digestive enzymes in their saliva, and some lines of snakes evolved such that those enzymes became more venomous to their prey.
2-how can creatures that didnt have eyes evolve into creatures that have eyes?
Some proteins can change configurations in response to light. If the changed configuration affects a signalling pathway in a nerve cell (either directly or because of signalling between the cell with the protein and the nerve cell) then the light will cause the nerve to fire an action potential. This could affect behavior of the organism in any number of ways. If the ways were beneficial, then the setup would be selected and improved on by natural selection. Groups of such cells near the skin would indicate the presence of light and its direction. By recessing those cells into a cup the directionality of the light could be made more evident. When (due to further selected mutations) the cup became more recessed and the opening closed to a pinhole, then crude images would be formed on the light sensitive cells. Clear cells for a lens and cornea would add clarity to the image. http://en.wikipedia.org/wiki/Plants#Evol…
> 3-how did trees and plants got created?
They evolved from green algae. http://en.wikipedia.org/wiki/Plants#Evol…
> 4 how do you know what happene 2 to 100 milion years ago?
Fossils and the patterns of genetic similarities in living species.
> 5- why is it that we have always to evolve rather than stay the same? and is ther any proof that the people that existed 800 years ago are different than the people now?
There could be stabilizing selection, which keeps certain characteristics from evolving. And people would be unlikely to have changed in noticeable ways in just 800 years.
> 6-how did apes evolve from bacteria?
By a long serious of small steps. - 22 hours ago
- Answerer 2
1. Toxins
and venoms are produced in a wide range of ways but they are chemicals produced
by the cells. There are cells in our body that secrete enzymes or hormones or
chemicals Like the strong acid in our stomachs, or the deadly toxins produced
by plants (which are often a lot more deadly than animals). We have lots of
pathways in our body that produces chemicals which are controlled by genes. If
there is a mutation that causes a new chemical to be produced which is more
effective than others produced by members in the same species, it will kill
more prey, eat more and be healthier and produce more offspring with the same
genes and they will pass it on...over time further mutations which may produce
even more deadly toxins.
2. Even single celled protists have an "eye spot" which are photosensitive and react to to light intensity. It is advantageous for cells or organisms to have photosensitive cells as light is often a vital part of the life, in that they are move towards it or move away from it. Even plants have cells and chemicals that are affected by light.
Those that had mutations that had changes which made their eyes or protoeyes more effective in that they can see better so they can react better then they would be more advantageous and have more offspring with those features and it would increase in the populations over time until they all have it.
3. long and complicated, but they have cells, different to animals, but there are still single celled phytoplankton which have chloroplasts which allow photosynthesis and provide food for the organism. In the same way animals evolved into multicellular animals from a single cell, that simple organisms with less cells than larger ones evolved first then over time more and more complex cells evolved.
4. This is not that long in geological terms but you can look at the rocks, the type of rock tells from an area can tell you a lot. You can look at the type of rock, eg sandstone (beach or desert), limestone (under the water), mudstone, coal (plant material), etc. You can see the pollen in the soil and fossils eg in the UK there is a lot of palm pollen, so it was a lot warmer in climate in the past than it is now, or you can see if there was grass pollen, pine, or whatever.
Then you can look at the fossils that lived in the area and put it all together. Fossils can be bones or amber or fossilied faeces (to see what animals ate) or footprints or shells or whatever.
You can see what happened to rocks eg water erosion might mean a river was in the area, uplift (mountain building) and erosion. The geology tells us what happened to the landscape
When you put it all together you get a reasonably good picture of what happened a while ago.
5. We KNOW that the past has changed, so we must be changing as well. We evolve because if we don't we would die. No change means less likely to survive any changes that occur.
6. well kind of in the same way, you, me and everyone else has already come from one cell to who you are today. Some people think that if you go back in time from an adult to a single cell, which is why the embryos of birds and fish and reptiles and mammals look the same as an embyro and even more so in the earliest developments after the zygote. A cell divides. Sometimes it stays close to its sister cell, kind of like conjoined twins. They stay together and grow together.
It is a pretty long and complex process.
2. Even single celled protists have an "eye spot" which are photosensitive and react to to light intensity. It is advantageous for cells or organisms to have photosensitive cells as light is often a vital part of the life, in that they are move towards it or move away from it. Even plants have cells and chemicals that are affected by light.
Those that had mutations that had changes which made their eyes or protoeyes more effective in that they can see better so they can react better then they would be more advantageous and have more offspring with those features and it would increase in the populations over time until they all have it.
3. long and complicated, but they have cells, different to animals, but there are still single celled phytoplankton which have chloroplasts which allow photosynthesis and provide food for the organism. In the same way animals evolved into multicellular animals from a single cell, that simple organisms with less cells than larger ones evolved first then over time more and more complex cells evolved.
4. This is not that long in geological terms but you can look at the rocks, the type of rock tells from an area can tell you a lot. You can look at the type of rock, eg sandstone (beach or desert), limestone (under the water), mudstone, coal (plant material), etc. You can see the pollen in the soil and fossils eg in the UK there is a lot of palm pollen, so it was a lot warmer in climate in the past than it is now, or you can see if there was grass pollen, pine, or whatever.
Then you can look at the fossils that lived in the area and put it all together. Fossils can be bones or amber or fossilied faeces (to see what animals ate) or footprints or shells or whatever.
You can see what happened to rocks eg water erosion might mean a river was in the area, uplift (mountain building) and erosion. The geology tells us what happened to the landscape
When you put it all together you get a reasonably good picture of what happened a while ago.
5. We KNOW that the past has changed, so we must be changing as well. We evolve because if we don't we would die. No change means less likely to survive any changes that occur.
6. well kind of in the same way, you, me and everyone else has already come from one cell to who you are today. Some people think that if you go back in time from an adult to a single cell, which is why the embryos of birds and fish and reptiles and mammals look the same as an embyro and even more so in the earliest developments after the zygote. A cell divides. Sometimes it stays close to its sister cell, kind of like conjoined twins. They stay together and grow together.
It is a pretty long and complex process.
- Answerer 3
http://en.wikipedia.org/wiki/Evolution
http://en.wikipedia.org/wiki/Human_evolu…
http://en.wikipedia.org/wiki/Human_evolu…
http://en.wikipedia.org/wiki/Snake#Evolu…
http://en.wikipedia.org/wiki/Evolution_o…
http://en.wikipedia.org/wiki/Plant
http://en.wikipedia.org/wiki/Evolutionar…
http://en.wikipedia.org/wiki/Bacteria
http://en.wikipedia.org/wiki/Timeline_of…
http://en.wikipedia.org/wiki/Evolutionar…
http://en.wikipedia.org/wiki/Human_evolu…
http://en.wikipedia.org/wiki/Human_evolu…
http://en.wikipedia.org/wiki/Snake#Evolu…
http://en.wikipedia.org/wiki/Evolution_o…
http://en.wikipedia.org/wiki/Plant
http://en.wikipedia.org/wiki/Evolutionar…
http://en.wikipedia.org/wiki/Bacteria
http://en.wikipedia.org/wiki/Timeline_of…
http://en.wikipedia.org/wiki/Evolutionar…
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