Cladistics and "Eclecticism"

[Thomas DiBenedetto]

-----Original Message-----
From: P.Hovenkamp
>Two questions, well, three actually:
>1. If a group of people (say, a mixed group of 100 men, women and children)
>embarked on a spaceship and were to settle on Mars - would that effectively
>split Homo sapiens into two species (assuming contact would be scarce and
>limited to raw materials, not frozen sperm etc.) the moment the spaceship
>took off?
>2. If a group of people (say, a mixed group of 100 men, women and children)
>embarked on a plane which later crashed into a high mountain in the Andes
>(alas, no survivors) - would the situation to us survivors on the ground
>(and in other planes) be different in any way from the situation we would
>have had in the first case?
>3. Considering the fact that (2) is a fairly common occurrence, are we
>still in the same species as we were this time last year?

Anyway, as far as I can make out from this post, your answers are Yes, No,
No.
***************
I guess my decision to save some time was a bad one. I should have simply
answered your questions.  My answers would be No, Yes , and Yes. I must be
pretty inarticulate to have given you reason to conclude the exact opposite.
I will try harder.

The criterion for demarcating species, as well as any other taxon, is
_relationships_  among groups. There is nothing that has changed from last
year to this year about the nature of the relationships between our species
and other species. So queston 3 is obviously Yes.  The establishment of a
new group, a new species evolutionarily isolated from us _does_ change the
nature of the relationships between our species and other species. So the
answer to question 1 would be Yes eventually - but since you stipulate "the
moment the spaceship took off" I would have to say No - not yet. I don't
know what the point is of trying to pin down the "exact moment of
speciation" - I don't suspect that that is something that could ever be
done, or that has much meaning. But I will stick with a "No, not yet" answer
because clearly the astronauts cannot be said to have established their new
species yet, in any real sense.
A group of people dying does not change the nature of the relationships
between our species and other species. So question 2 is clearly Yes.

What's your point?

Tom DiBenedetto