05.05.09
Charles Darwin & Natural Selection
7th Graders,
For the rest of the week, you will be studying Charles Darwin and The Theory of Natural Selection.
- Watch the video “Elements of Science – Biological Evolution” as a class.
- Post a reaction to two of the discussion questions to the comment section of the blog. All posts should be unique and well though out. Feel free to use your textbook and my links to answer the discussion questions. (All comments should be at least 4 sentences and should contains new ideas that no one else has posted).
- Complete the Charles Darwin Webquest turn in your data log sheet and quetions to Cinderella.
Discussion Questions
- How do you think natural selection and evolution relate to disease spread (like swine flu)?
- Does evolution ever occur so quickly that it can be easily observed in one species?
- What are some of the struggles of using fossil records to support the theory of evolution? Does this effect how you feel about the theory?
- Geologists think that the earth is roughly 5.6 billion years old. How do you think they arrived at this number?
- Scientists believe that early life first formed in conditions similar to deep ocean hydrothermal vents. Why would life be different there then in our ecosystem?
Helpful Links
- Take a Trip with Charles Darwin
- Understanding Evolution (Berkeley)
- The Complete Works of Charles Darwin
-Mr. K
May 6, 2009 at 8:59 am
2. In some cyanobacterial cells, evolution can be easily observed. They reproduce so rapidly amongst themselves that they can evolve very quickly, and these changes can be observed. In humans, reproduction takes much longer, and there are too many humans in the gene pool to really observe evolution. In bacteria, evolution can be observed, but in humans, because of the enormous size of the gene pool and because of the slowness of reproduction, evolution is more difficult to be observed and many doubt that it even occurs at all. If it does occur, it surely does so at a very slow rate.
1. Natural selection and evolution relates to swine flu in that some are mutated so that they are weaker and more susceptible to the disease. Others are mutated so that they are stronger. Those that are mutated to be weaker will get the disease and those who are strong will not. In essence, mutations drive the spread of disease.
May 6, 2009 at 8:59 am
2. Evolution can occur so quickly that it can be seen easily in very few species. This happens in some bacteria cells, who can reproduce in about twenty minutes. Others take hundreds of years. Either way, all species will reproduce, whether they will survive is a different question.
4. Scientists arrived at this number by looking at the physical evidence left behind. I mean this in the way that scientists can look at the rocks and fossils from the past. They can date how much change their has been in certain rocks, such as the Grand Canyon. They can date how long a fossil has been in its place. Together, these ways give them an accurate date, maybe not exact though, but close.
May 6, 2009 at 9:01 am
2.) Yes
4.) I think scientist came up with that length of time because of the evidence of fossils that were buried beneath the earth. the genetic materials in the fossils show age and evolution.
May 6, 2009 at 9:01 am
2. Yes
4. I think they estimated the number because no one actually knew the real number of how many years it was. There was never a scientist that was right about the years, all of them just estimated the amount. Also I think that they have observed the fossils and determined a number of how many years this fossil has been buried in the ground.
May 6, 2009 at 9:02 am
It is possible to observe evolution in one species.
Geologists have looked at very old rocks and have determined that the oldest rocks found have been 5.6 billion years old.
May 6, 2009 at 9:02 am
2. Yes evolution can be easily observed. But it cannot be observed in all organisms. The only organisms that can be observed are ones that reproduce very quickly (such as bacteria). Scientists will be able to notice the small mutations in organisms like those.
4. Scientists can determine the age of the earth in few ways. One way is to determine how long it takes a rock to form and then observe mountains and plateaus. They can also see fossil structures.
May 6, 2009 at 9:03 am
Evolution usually occurs very slowly and it will not be as easy to observe many differences of the live species of the past and today.
They must have estimated how the earths resources must have been really quick.
May 6, 2009 at 9:03 am
Hey Mr. K!
Hope you are all having fun in DC.
Here are the answers to questions 4 and 5.
4. I think that scientists arrived at this number by having archaeologists find fossils and using carbon dating to find approximately how old the world is. I still don’t think this is a very accurate measurement.
5. Life would be very different in the hydro thermal vents. There would not be any oxygen there, there would not be any light and there would not be much life that was very developed. On the other hand, in our ecosystem there is oxygen and light from the sun.
~Natalie =D
May 6, 2009 at 9:07 am
5.) Life would be most different in that ecosystem then in ours because for one it is under water and because of that the life there probably breaths with gills while we breath with lungs. The plants there are probably things like seaweed and coral probably thrives to give the fish food. The animals there probably are not exposed to much light because the hydrothermal vents are so deep in the ocean.
2.) Evolution may occur so quickly that it can be easily observed in one species. It doesn’t happen often but one example would be viruses that evolve to over come new medications.
- Emma R.
May 6, 2009 at 10:25 am
2.) Some forms of evolution can be observed. Cells can evolve in a week, day or even a year.
4.) Scientists probably came up with that the world was 5.6 billion years old because you can see all the layers in canyons, or cliffs. They have methods of finding out how old things are, like carbon dating.
-David Lindner
May 6, 2009 at 10:28 am
2. Yes. Bacteria evolves very quickly and if you watched it’s development for awhile, you would probably see changes.
4. Scientists can look at rocks and fossils and date them. (maybe inaccurate but it’s the best we got) This is how they came to the number 5.6 billion.
May 6, 2009 at 10:30 am
1.) I think natural selection and evolution relate to disease spread because natural selection makes it easier for organisms to survive to produce offspring, and evolution changes how organisms are and when organisms change, they are prone to different diseases, so it takes a while for antibiotics to be made in order to fight off whatever disease spread it is.
2.) Evolution occurs so quickly that it can be observed in one species, this species is bacteria.
May 6, 2009 at 10:31 am
Anjali Khatri
2. Does evolution ever occur so quickly that it can be easily observed in one species?
Yes. It can be observed in bacteria.
5. Scientists believe that early life first formed in conditions similar to deep ocean hydrothermal vents. Why would life be different there then in our ecosystem?
All the creatures would be water creatures. There would be no land creatures.
May 6, 2009 at 10:31 am
2.) Yes evolution can occur so quickly that it is easily observed in one species. You could probably most easily observe quick evolution in different types of bacteria. Some bacteria can reproduce very quickly, while some take a long time.
4.) I think that scientist came up with that number in one of three ways. One way is they studied rocks and plateaus as they formed. They studied how long it took mountains to form, and lastly they studied the different fossils they discovered.
~Chris
May 6, 2009 at 10:32 am
2. yeaz
4. I think scientist came up with that length of time because of the evidence of fossils that were buried beneath the earth. the genetic materials in the fossils show age and evolution.
May 6, 2009 at 10:33 am
2.) Yes, some forms of evolution can be observed. But it can only observe bacteria because it reproduces quickly.
4.) I think that they estimated the number of years because no one really knows how old the rocks really are.
May 6, 2009 at 11:22 pm
Great Start 7th grade!
You all did a good job of answering question 2. Now tackle some of the other questions. Be specific and take a stance. You will be graded on the completeness and accuracy of your answers. I recommend doing RESEARCH to form a hypothesis.
-Mr. K
May 7, 2009 at 11:37 am
I think that SuZ is right. She had a good post.
May 7, 2009 at 11:39 am
2.Does evolution ever occur so quickly that it can be easily observed in one species?
Answer: Yes, in bacteria.
4.Geologists think that the earth is roughly 5.6 billion years old. How do you think they arrived at this number?
Answer: They looked at old rocks and fossils that around the same age of 5.6 billion years old.
May 7, 2009 at 11:41 am
Dear jacoby,
I agree with you on your post. It was very thought out and well written. I agree with you 100%.
From,
Chris
Oh and Mr. Kremer we were kind of confused on what we are supposed to to do so if this isn’t right…we’re sorry…
May 7, 2009 at 11:54 am
2. Evolution takes hundreds of years for even slight changes in mammals to take place. This is obviously too slow to observe evolution in mammals. But what about microorganisms? Viruses and cells are able to adapt in the enviorment in a matter of hours to a little more than a day. But this takes lots of patience for scientists, but it can be done!
5.If we were living in conditions similar to early life on earth, we would be completely different from today. We would have to stand extremely high temperatures. This means that our body temperatures would have to be very high. Also, there would be very little land. We have have to have gills to breath, and water dynamic body structures. We may even have to have special skin so it wouldn’t disintegrate in the water!
May 7, 2009 at 11:56 am
I agree with Jake’s comment completely. Survival is crucial.
May 7, 2009 at 1:55 pm
Dear David:
For your answer to question #2, I believe that bacteria is an example of this fast evolution. It can evolve in 20 minutes.
May 7, 2009 at 1:56 pm
Yah… I agree with Reagan!!!! It will not be easy to observe the differences of the live species of the past and today!
May 7, 2009 at 1:57 pm
I agree with Charlie, because he copied me exactly!!!!!
May 7, 2009 at 1:58 pm
Hey Mr. K!
I agree with Suzy in #2 that bacterial cells can reproduce so fast that evolution can be seen through bacteria reproduction.
~Natalie =D
May 7, 2009 at 1:59 pm
I think Natalie was right with her answer to Number 5. In a hydrothermal vent, life would be very, very different.
May 7, 2009 at 2:01 pm
Hey Nat!
I agree with your post on both of the questions. They seem reasonable and unique to me. I like what you put about the hydrothermal vents. I also like the concept of using carbon dating to find out how old the Earth roughly is.
May 7, 2009 at 2:03 pm
I agree with Anjali that evolution can occur so quickly that bacteria can observe it.
May 7, 2009 at 2:06 pm
I agree with Chris’ answer for number 4. I like how he gave three ways that geologists can find out about evolution.
May 7, 2009 at 2:07 pm
sorry Mr. K I posted incorrectly here are my answers to 2 and 4
2. Yes i do believe that evolution can occur so quickly that bacteria can observe it.
4. I think that scientist came up with the Earth being 5.6 billion years old by studing fosslis and calculating the year of those fossils.
May 7, 2009 at 2:42 pm
matt, dont forget that they can look at rocks and determine their age and use this to determine the age of the earth
May 7, 2009 at 8:40 pm
Class,
A response should either be an extension of an idea, a thoughtful question, or a counterpoint. Don’t just agree with them!
-Mr. K
May 11, 2009 at 7:15 am
I would like to add to my comment.
2.Evolution can occur so fast that it be observed in one species. Evolution can be observed in bacteria.
4. Scientists can look at rock formations in places like the Grand Canyon and determine events that happened to the earth billions of years ago. They can also test rocks to see how old they are. Scientists can even look at fossils to observe what life was like billions of years ago on planet earth.
May 11, 2009 at 7:18 am
Mr. Kremer,
On Friday I wasn’t able to get onto the webquest. If you can help me get onto it then I can stay after school to work on it.
May 11, 2009 at 10:34 pm
Hey Mr. Kremer,
Here are the answers to 2 of the discussion questions…
2) Evolution occurs extremely quickly in bacteria and people can observe it. Almost all other living things reproduce too slow for people to observe evolution of that species. Also I agree with Emma when she said viruses evolve very quickly to adjust to the medicines people take. I don’t know if people can actually observe viruses evolving but it happens fast enough that someone could observe it.
4) Scientists look at fossils and rock formations like cliffs or canyons. They test them to see how long they have been around. They can also test regular rocks that they maybe found underground to see how long those rocks have been there.
and for the responding to someone else’s post…
Claudia, bacteria don’t observe evolution… people observe the bacteria evolving…
-ana k.