Palm frond... just because I'm in an obvious sort of mood.
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3 years ago
Monday, June 23, 2008
Paleo 101 Rambling Post on Uniformitarianism
Uniformitarianism is usually the cornerstone of any class in geology or paleontology. Wikipedia (of all places) has a pretty good definition.
This usually just summed up as "the present is the key to the past". I don't really like summing it up though because it glosses over something very very important: Uniformitarianism is an assumption. When I look at ripple marks in a 300 million year old sandstone (see below)
I assume they form in the same way ripple marks form today by water running over sand making little "waves" in the sand (I'm NOT a sedimentologist can you tell?) See below:
Like I said this is an assumption but I think it's a valid assumption. Really it's not more of an assumption than any scientist makes. More fundamentally uniformitarianism means that the "rules" don't change. What ever laws of physics operate to make ripples today operated in the past to make ancient ripples.
Wait a second.
That's the fundamental assumption that underlies ALL of science. If we didn't assume that the laws of nature don't change then there would be no way to figure anything out, no way to do science. So why do geologists and paleontologists make such a big deal out of it? (believe me we do, we gave it a big name and we talk about it a LOT). I mean it's not like in chemistry the Professor says " ok the ideal gas law states that pv=nrt and it has ALWAYS been that way. ??? No, pv=nrt it just does and you assume it always has.
Geologists and paleontologists have had to deal with something that chemists and physicists do not: People who think the Earth is 6,000 years old. What geologists are really saying when we talk about uniformitarianism is: "if you are going to insist on believing the Earth is 6,000 years old then you're also going to have to believe that the laws of physics change significantly because there is no way that the rock that is on the surface of the Earth today could have formed in 6,000 years"
Now my guess is that people who believe this who believe the 6,000 year time frame would just call the suspension of the laws of physics a miracle and get on with their lives. But if that's the case then what's the point of any kind of science? What's the point of anything? Why get up in the morning if gravity may well stop working at any time or why dry to drive as your car relies on the ideal gas law and it may stop working.
Ok this has degenerated a bit so here's the crux:
Uniformitarianism just means that the laws don't change... for anyone, not for physicists or chemists or geologists. So when geologists look for explanations for what we see in the rock record we look to what's going on now. Because the processes that are acting now are the same as the processes that were acting then.
the assumption that the natural processes operating in the past are the same as those that can be observed operating in the present.
This usually just summed up as "the present is the key to the past". I don't really like summing it up though because it glosses over something very very important: Uniformitarianism is an assumption. When I look at ripple marks in a 300 million year old sandstone (see below)
I assume they form in the same way ripple marks form today by water running over sand making little "waves" in the sand (I'm NOT a sedimentologist can you tell?) See below:
Like I said this is an assumption but I think it's a valid assumption. Really it's not more of an assumption than any scientist makes. More fundamentally uniformitarianism means that the "rules" don't change. What ever laws of physics operate to make ripples today operated in the past to make ancient ripples.
Wait a second.
That's the fundamental assumption that underlies ALL of science. If we didn't assume that the laws of nature don't change then there would be no way to figure anything out, no way to do science. So why do geologists and paleontologists make such a big deal out of it? (believe me we do, we gave it a big name and we talk about it a LOT). I mean it's not like in chemistry the Professor says " ok the ideal gas law states that pv=nrt and it has ALWAYS been that way. ??? No, pv=nrt it just does and you assume it always has.
Geologists and paleontologists have had to deal with something that chemists and physicists do not: People who think the Earth is 6,000 years old. What geologists are really saying when we talk about uniformitarianism is: "if you are going to insist on believing the Earth is 6,000 years old then you're also going to have to believe that the laws of physics change significantly because there is no way that the rock that is on the surface of the Earth today could have formed in 6,000 years"
Now my guess is that people who believe this who believe the 6,000 year time frame would just call the suspension of the laws of physics a miracle and get on with their lives. But if that's the case then what's the point of any kind of science? What's the point of anything? Why get up in the morning if gravity may well stop working at any time or why dry to drive as your car relies on the ideal gas law and it may stop working.
Ok this has degenerated a bit so here's the crux:
Uniformitarianism just means that the laws don't change... for anyone, not for physicists or chemists or geologists. So when geologists look for explanations for what we see in the rock record we look to what's going on now. Because the processes that are acting now are the same as the processes that were acting then.
Wednesday, June 18, 2008
... the stupid assignment
Ok ok I know I'm fixating on this student BUT. My problem child came up to me today and said "I tried to do the stupid earthquake assignment"....
This may require more self control than I have.
This may require more self control than I have.
Tuesday, June 17, 2008
Just in case
If someone out there has an extra 850 dollars laying around (yeah right)
I take a 60 cm frame
(HEY ... it's worth a try .. you never know... )
I take a 60 cm frame(HEY ... it's worth a try .. you never know... )
Politics
Ok I really wasn't going to go here but: Barak Obama just did an interview in the Wall Street Journal in which he said:
I tend to be eclectic. I do think we're in a different time in 2008 than we were in 1992. The thing I think people should feel confident in is that I'm going to make these judgments not based on some fierce ideological pre-disposition but based on what makes sense. I'm a big believer in evidence. I'm a big believer in fact. You know, if somebody shows me we can do something better through a market mechanism, I'm happy to do it. I have no vested interest in expanding government or setting up a program just for the sake of setting one up. It's too much work.QUICK someone elect him president before he changes his mind!!!!!!
Thursday, June 12, 2008
speechless
I have a student who has left me just speechless. She is utterly without... I don't know ... curiosity... I'm just amazed and just sort of taken back. She's been on me all semester about how she doesn't "do" math or tests. By not dong math she means not doing arithmetic I was talking about relative humidity and I wrote 5/10 and got 50% and she stopped me because she didn't understand. (remember I teach COLLEGE) So as the rest of the class groaned I went through the whole thing... feeling like I was teaching 5th grade.
Then yesterday ... she came to me after class to tell me she can't do the writing assignment. I asked her what she thought of the reading associated with the assignment. She said "Oh yeah I read that it was boring I didn't really think anything about it." I was just dumbstruck. How can you read something and not think ANYTHING about it??!!?? hell I think something about the damn phone book when I read it (Look at all those Smiths I wonder why that is?) she just managed to read a 5 page essay on the faith and science as and not think anything about it.
I think the girl has a serious future in politics
Then yesterday ... she came to me after class to tell me she can't do the writing assignment. I asked her what she thought of the reading associated with the assignment. She said "Oh yeah I read that it was boring I didn't really think anything about it." I was just dumbstruck. How can you read something and not think ANYTHING about it??!!?? hell I think something about the damn phone book when I read it (Look at all those Smiths I wonder why that is?) she just managed to read a 5 page essay on the faith and science as and not think anything about it.
I think the girl has a serious future in politics
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