Vorkosigan

Thank you! I made this point over and over in my history and philosophy of science seminars. I tried to steer people into the cognitive sciences, but.....

Vorkosigan

Let's take common descent as a fact. There are two lines of evidence:

1) DNA evidence

2) morphological evidence

Note that these are independent of each other -- common descent was deduced long before DNA, and DNA confirmed the results obtained by morphological studies, with a few surprises in the details.

Note that common descent was already recognized before Darwin. In fact, changes in organisms over time posed major problems for 18th century biologists, and they wrestled with how to explain and classify both morphological change and extinction. See, for example, the work of Linnaeus, John Ray, Cuvier, Harvey,d'Holbach, Bonnet, Robinet, de Maillet.....

The DNA evidence is basically incontrovertible.

Vorkosigan

caritas

John Galt Jr wrote,
Even without an historical record an arborist (like, e.g. me) could tell you whether the trees in your yard got there via landscaper or nature. Simply put, nursery-grown then transplanted trees generally retain abundant evidence of their origin. This tree's root archetecture (sp?) will likely be greatly influenced by the container (or series of increasing-sized containers) in which it was grown at the nursery. I might even be able to determine whether the tree was planted as balled-and-burlaped or from container stock; if container whether as 3 gallon or 1 gal; if 1 gal whether from a round or from a square 1 gal. pot; whether at the nursery the plant had been potted on from a 4 inch square to a 1 gal. round pot. True, the better landscapers (a minority in my part of the country) take the time to spread the roots of pot-bound specimens thus reducing the evidence of nursery origin at the same time as they improve the tree's chances of thriving. Still some tell-tale signs to differentiate it from a nature sown seedling will likely remain. An air spade (uses compressed air bursts) can quickly nondestructively excavate the root crown area for examination.
Your analogy parallels (I don't know if you intend this) the oft repeated creationist retort of "So, were you there millions of years ago to observe these alleged events?" Paleontologists have reason to be confident in their interpretations of fossil species despite not having been there for the same reason that arborists have confidence in their interpretation of origins of trees in a landscape despite no writen record or benifit of having been there at time of lot development.
[QUOTE]
Robert

Quetzal

caritas: Welcome, and excellent analogy!. I've been looking for an accessible everyday example showing how science works in response to the "you weren't there" rhetoric. Your reply is right on the money!

In short, specialists who devote their careers to examining minute details of a particular field CAN in fact tell the natural history of an organism (for ex) or fossil by the very same method you used - certain details are going to be this way if A is true but not that way. That way implies that B is true, rather than A.

May I use your analogy in the future?

Duvenoy

Welcome Caritas!

What an interesting and informative post! I never knew that you could tell so much about a tree with such seemly simple procedures (I said: "seemingly." Many things appear simple to the layman).

Now, how do I get rid of mimosas? <img src="graemlins/banghead.gif" border="0" alt="[Bang Head]" />

doov

Coragyps

Doov - I've heard that napalm or tactical nuclear weapons will help a little with mimosas....

caritas: What Morpho said! Welcome!

RufusAtticus

&lt;Raises Hand&gt;
Umm, excuse me. Do you know any biologists or are you just pulling things out of you butt?

I am an evolutionary biologist, and I work with evolution every day. Evolution is a fact.

Do you need any more confirmation for the opinions of scientists?

~~RvFvS~~

caritas

Hi Morpho,
Thanks for the welcome. Yes, please feel free to use that analogy. I'm not even a specialist, just a "general practice (tree) doctor" arborist who spends 10% of my time helping clients with basic root problems in the landscape ( a great break from being 50 feet off the ground covered in spruce pitch). Almost any competent working arborist with a passion for tree health and a willingness to stay fairly current on root research being done by the specialists will have a working knowledge of this stuff.
Robert

caritas

Hi Duvenoy, Coragyps
Thanks for the welcome. The detail of root analysis I do is truly basic stuff compared the intimate knowledge of tree life history folks like Dr Costello (U of Calif, Coop Extension) and Dr Shigo (U of Oregon ?).
As to getting rid of Mimosa (Albizia julibrissin), any unwanted woody plant can be starved out if cut to the ground repeatedly each time it regrows about 12 inches. Should take about 3 years. Tough to take a vacation though

Duvenoy

Hi again, Caritas.

"As to getting rid of Mimosa (Albizia julibrissin), any unwanted woody plant can be starved out if cut to the ground repeatedly each time it regrows about 12 inches. Should take about 3 years. Tough to take a vacation though"

I've been whacking the miserable sons of bitches ever since I moved in here; the smaller ones in places where I can't get at them with a lawnmower. I like the big tree. It's in bloom now, and very pretty.

This spring, when the ground was soft, I chained the stumps to the 4X4 Chevy and yanked them out (not as easy as it sounds). I will be damned if there are not some coming back! I've taken to calling it the Jesus Tree.

Guess I'll just have to keep at it.

Thanks,

doov