You do that Archie.

How about an analogy of yourself with a compound personality?


"Archimedes Plutonium" wrote in message
...


Monique Reed wrote:

Archimedes Plutonium wrote:

So my question today is how did anyone come to realize that a
blackwalnut leaf was compound with many green blots?

It is purely a matter of structure. Leaves usually have buds in their
axils (the angle between leaf and stem). These buds will produce
additional shoots, leaves, or flowers. Something with simple leaves
has buds in every axil. Something with compound leaves does NOT have
buds in the axils that the leaflets make with the axis of the compound
leaf. That is how you tell--look for the axillary buds. Whatever is
beyond the axillary bud is all one leaf.

Does compound leaf mean the blackwalnut was a recently evolved tree
and
that noncompound leafed trees are geologically older.

It is generally believed that simple leaves are the more primitive
form and that compound leaves represent the derived state. This
character has arisen independently in different groups many, many
times. (That is, one cannot say that all plants with compound leaves
share a common lineage or that all plants with compound leaves are
older than all plants with simple.)

And what survival value is it to a tree to have compound leaves rather
than noncompound?

In some cases, having finely divided leaves can break up air flow over
a leaf, reducing transpiration. This can be an advantage in dry
climates. In other cases, there does not seem to be an advantage--or
a drawback. Not every feature of an organism is beneficial or
harmful--many are neutral until some change in environment selects for
one state or another.

Or is this compound leaf thing just semantics with no biological
difference from say oak leaves or rose leaves or apple leaves.

No, not semantics. Morphology. Have a look at a flowering plant
systematics textbook--it will tell you about simple and compound
leaves.

Monique Reed
Texas A&M

I am trying to think of an analogy for animals in the manner that compound
leaves are to trees.

I wonder if any animals were borne with extra hands or extra fingers. I
wonder if any animal
was borne with extra eyes.

I wonder if any animal was borne with a compound heart, or extra heart. I
believe it was
reported that a horse had two hearts but did not pass that trait on.

I am looking for a analogy in animals that somewhat matches compound
leaves in plants.

Archimedes Plutonium
www.iw.net/~a_plutonium
whole entire Universe is just one big atom where dots
of the electron-dot-cloud are galaxies