Traveller-digest       Sunday, August 1 1999       Volume 1999 : Number 911



(R)1996. Traveller is a registered trademark of FarFuture Enterprises.
All rights reserved.

The following topics are covered in this digest:

Re: Back.....crasser than ever! 
Re: Test
Yet more filk
Re World Builder Deluxe
Multi-system Polities
Xenobiology - check this out
Re: Multi-system Polities
Re: Average Density of Cargo?
Re: Test
Re :- the Inyx and the Devi Intelligence
Xenobiology 101 : Ecology, Environment, and Evolution (long)

----------------------------------------------------------------------

Date: Sun, 01 Aug 1999 14:45:46 -0400
From: "Keven R. Pittsinger" <jamstar@accesstoledo.com>
Subject: Re: Back.....crasser than ever! 

> >Mick was going to be working on a SVGALIB version after porting it to FPK,
> >but he kinda dissappeared over the Australian summer there...  If you
> *DON'T*
> >have FPK yet, *GET IT*!!!  It's a TP workalike for Linux & Windoze.  It's
> at:
> 
> I just tuned back in and...sniff...it's good to be missed...sniff....

We were beginning to wonder if we were gonna have to send a diplomatic 
mission to get you back from the kangaroos or something, dood...
 
> Seriously though, work commitments have _really_ cut into my available time,
> but now that I'm off shift work, I'll be paying a lot more attention to the
> list than I have over the past six months.  I'm also writing freelance, and
> studying part time, so I guess thwe amazing thing is that I have any free
> time at all.  Except for the Pub...I've _always_ got time for the pub.

Heheh.  Priorities, dood, priorities...
 
> I'm still chucking the Linux conversion around Kev...I kinda got sidetracked
> learning Java.  The GTK+ toolkit for FPK will help get me back on track
> though.

How's the basics coming on the port?

Keven

- -- 
tc++ tm+ tn t4- to ru++ ge+ 3i c+ jt au st- ls pi+ ta+ he+ so- vi zh sy
- ------------------------------------------------------------------------------
                                                     Science-Fiction Adventure
                                                     In Reavers' Deep

------------------------------

Date: Sun, 1 Aug 1999 14:51:05 -0400
From: "Sword Worlder" <swordworlder@clinic.net>
Subject: Re: Test

- ----- Original Message -----
From: Keven R. Pittsinger <jamstar@accesstoledo.com>
> Been getting some weirdness in my system here.  Just testing to see if I
got
> rid of it...

Nope.  Weirdness is still there, Kev.  :-p


^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
The TRAVELLER Domain
http://www.downport.com
Colin Michael, Webslinger

------------------------------

Date: Sun, 01 Aug 1999 11:56:06
From: "Douglas E. Berry" <dberry@hooked.net>
Subject: Yet more filk

Since my last attempts weren't greeted with death threats, allow me to
inflict this one on you:

       The Traveller Saga
   Douglas and Kirsten Berry
(music: American Pie, by Don McLean)

A long, long time ago,
I can still remember how the first game stirred my soul
Known Space on the StarForce map
A fist of stolen dice and that[1]
Was all it took to make my dreams take flight

Every weekend at the game store
With my ten hard-earned bucks to buy more[2]
Now twenty years have flown past
Of wars and life and mishaps
I know I'm not that wide-eyed teen
But I still look up and I still dream
Whatever comes I do believe
I still will play this game

(Chorus)
So say hey, this here Traveller game
The rules set may be changing
But the concept's the same
And it lets me travel through the stars and through time
Saying: Gonna play this game 'til I die
Gonna play this game 'til I die


Do you remember when CT
Was only Books 1,2, and 3
and a homespun setting that you wrote
Do you recall Bill and Andrew Keith
Early FASA and JG[3]
All the products out to help us play
And slowly the Imperium came to light
With enemies for us to fight
Then in Supplement 3
We met the Zhodani
It was a glorious time of change and growth
And we couldn't ever get enough
So we sat down and wrote our own stuff
And I still played this game

(Chorus)

Then came some folks called DGP
About as passionate as you or me
About this universe we'd made
They filled in all the holes and cracks
They fixed some rules, they wrote a patch[4]
And changed the way the game was played
But GDW had a plan
Strephon died at an assassin's hand
The Imperium fell to war
Much worse than before[5]
And in '87 we got MT
To play through this galactic catastrophe
But the new rules didn't mean much to me
'cause I still played the game

(Chorus)

For six years, we played through Hard Times
While pretenders fled and planets died
And we wondered how it all would end[6]
Then we got the horrid news
about a Virus that would use
any means to kill humaniti
TNE made its bright debut
While the Old Timers hissed and booed
Much dissent was spoken
The TML was broken!
And while X-Boat waxed on days gone by[7]
GDW up and died
The hard core fans sent up a cry
They can't have killed our game[8]

(Chorus)

Then Marc Miller took back control
And promised Traveller like we had before
But did they try to push too fast?
For T4 was a sorry mess
Barely edited and the rest
Of the releases, well they didn't shine much more[9]
The authors grumbled we've not been paid
Imperium Games quietly sped away[10]
Then Loren brought our reprieve
A deal with Evil Steve
A return to all those Classic themes
Of hard-sf and future dreams
It may be GURPS, but what the beans?
I still will play this game[11]

(Chorus)

<slowly>
Now twenty years and more have past
From first edition to the last
But the setting is the game to me
I went down to my local store
Where I bought the first books years before
But that store now is part of history[12]
And nowadays the kids play Magic
Superheroes or Vampires tragic
No more the sound of parties-
The quiet hum of PCs
And books for which I once did lust
Sit on the shelf collecting dust
But I have them and that's enough
For still, I play this game

(Chorus)

(Chorus)

Notes:

[1] My very first game was played on the map from SPI's StarForce game,
using Larry Niven's Known Worlds.  Besides the two dice provided in the
box, we raided every board game in the house for extra six-siders. Craig
was the Ref, and I played Beowulf Shaeffer.  I still remember how the last
session ended.  I was mind-controlled by a Grog.

[2] Personal note: As a teenager, I would make $10 a week for cleaning the
house.  I would then spend two hours on buses to blow the remaining eight
bucks on Traveller products.

[3] FASA (publishers of Shadowrun and Battletech) started out as one of the
tiny Traveller support publishers.

[4] Digest Group Publications was yet another fan-run Traveller support
company.  The difference was that they did incredibly good work.  For a
time in the mid-80s, they were responsible for most of the quality
Traveller material out there.

[5] In 1987 GDW killed off the Emperor Strephon to ignite the misnamed
Rebellion setting for MegaTraveller.

[6] The eventual resolution of Rebellion was a hot topic on the early TML.

[7] The use of GDW's House System, plus the odd nature of Virus, and the
complete change of setting and assumptions caused a major rift in Traveller
Fandom.  The Traveller Mailing List was actually broken into two separate
lists: X-boat, for classic/MT only, and the TML for all versions of Traveller.

[8] In 1995, Game Designers' Workshop closed it's doors after twenty years
in business.  This of course caused much debate on the fate of Traveller.

[9] Marc Miller's Traveller (aka T4) was an ungodly mess of poor editing,
awful layout, questionable artwork...

[10] To the best of my knowledge, nobody was ever paid for any freelance
work done for IG.  I wasn't.

[11] When GURPS Traveller was announced, some people took great exception
to the very idea of learning GURPS.  Others took a more casual approach.

[12] The Game Table, Campbell, California.  Remains the best gaming store I
ever knew.  Closed sometime in the mid-eighties while I was in the Army.

Final Note: My spell checker thinks that the most probable replacement for
"MegaTraveller" is "meatball".  Make of this what you will.
- --

Douglas E. Berry         dberry@hooked.net
 http://www.hooked.net/~dberry/index.html

"I created the universe; give ME the gift certificate!!"
                   - Lisa Simpson, Overachiever

------------------------------

Date: Sun, 1 Aug 1999 22:05:46 +0100
From: "Derrick Jones" <dojones.whitestar@btinternet.com>
Subject: Re World Builder Deluxe

Terry C wrote:
>....

>>stuart.ferris@virgin.net
>>http://freespace.virgin.net/stuart.ferris/index.htm

>It's terrific. I'm about to send a group of PC's (IISS External Mapping
>Branch) into Aslan space to do an extensive survey. Their mission will
>require that I have detail system stats, as well as an interesting series
of
>plot lines to tie it down.  I can see that WB will allow me to spend more
>time preparing my plot lines and less generating system stats.

This is exactly the reason I got involved in the project some time back.
My PC's were 'requested' as part of their 'Detatched Duty' to go exploring
and filling in maps and patchy survey areas in Foreven, Far Frontiers,
Beyond and Vanguard Reaches, (and further afield if thier trusty Donosev
will let them!)

One very good thing is that using the Random Number Seeding aspect of WBD,
all of my players can have the source details on their PC's to do the write
ups
for their reports out of game time. (They've made 'interesting' reading).

Because of the seeding, they can run WBD on their machines and get exact
replicas of the information that I have here. I trust them to only look at
what they're
supposed to (ie what their characters can determine from surveys)

The only real problem is that I need more hard disk space, (particularly if
Stuart
successfully does the world mapping routines he keeps promising)


I'm glad you like it, I've enjoyed working on it!

Cheers

Derrick

------------------------------

Date: Sun, 01 Aug 99 17:09:52 -0500
From: "Eris Reddoch" <eris@pcola.gulf.net>
Subject: Multi-system Polities

In my Akus Moby PBEM, the characters know of three multi-system
governments.  The CSA is a confederation, the Montrose Collective is
a...um, sort of a federation, and only the Zeristu Empire is a true
Empire.  There are others further out that they haven't heard of
yet.  Most of them won't be true empires.

We need a better *general* name for multi-system polities than
"empire" or "pocket empire."  Something general that can be used to
refer to *any* multi-system polity. 

Any suggestions?

Eris
- -- 
- -----------------------------------------------------------
"Eris Reddoch" <eris@pcola.gulf.net>    using MR/2 ICE #245
The Quental Main@ http://www.crosswinds.net/~erisr
- -----------------------------------------------------------

------------------------------

Date: Sun, 01 Aug 1999 15:55:17 -0700
From: "Benyamene' ZeAbe' Akella" <xrp@sierratel.com>
Subject: Xenobiology - check this out

http://www.sierratel.com/aum/BZAT/FARCAST/Farcast.html

This page has detailed (though not yet complete) descriptions of the aliens
of the "Farcast" Sector (a sector IMTU, some distance spinward of the
Spinward Marches), their biology, history, cultures, governments, social
intercourse, and illustrations.

One of my major goals (aside from good background for gaming) is believable,
truly *alien* aliens.

This is a work in progress (updated usually daily), and I would appreciate
any suggestions, comments or constructive criticism from the list.

Thank you VERY much!

- -BZA

------------------------------

Date: Sun, 01 Aug 1999 16:08:08
From: "Douglas E. Berry" <dberry@hooked.net>
Subject: Re: Multi-system Polities

At 05:09 PM 8/1/99 -0500, you wrote:

>We need a better *general* name for multi-system polities than
>"empire" or "pocket empire."  Something general that can be used to
>refer to *any* multi-system polity. 

Just call them MSPs.
- -- 

Doug Berry
dberry@hooked.net
http://www.hooked.net/~dberry

------------------------------

Date: Sun, 01 Aug 1999 19:05:42 -0600
From: "David J. Golden" <goldendj@pcisys.net>
Subject: Re: Average Density of Cargo?

At 08:07 AM 8/1/99 -0600, you wrote:
>Side issue: has anyone (former Air Force loadmasters, maybe?)
considered
>weight and balance in the design of starships and the stowage of
freight?
>Specifically: can the use of artificial gravity and/or contragravity
>compensate for unbalanced loads -- both design loads and cargo --
and if
>so, how? 

	I've always assumed balance taken into account in loading the
starship, and that you could (and did) compensate in flight by
shifting fuel around between different tanks. In fact, that's one of
my "stock" malfunctions: something goes wrong with the automatic
balancing system; all piloting tasks are +1 difficulty (trying to
compensate). More of an annoyance than a life-threatener.
- -- ------------------------------------------------------------ --
   Dave Golden                  http://www.pcisys.net/~goldendj 

   Fight Spam! Join CAUCE! == http://www.cauce.org/

------------------------------

Date: Sun, 01 Aug 1999 19:06:29 -0600
From: "David J. Golden" <goldendj@pcisys.net>
Subject: Re: Test

At 02:38 PM 8/1/99 -0400, you wrote:
>Been getting some weirdness in my system here.  Just testing to see
if I got 
>rid of it...

	Oh, right. That's it. Send US the weirdness. That's *just* what we
need.

	Hmm ... how would we tell the difference?
- -- ------------------------------------------------------------ --
   Dave Golden                  http://www.pcisys.net/~goldendj 

   Fight Spam! Join CAUCE! == http://www.cauce.org/

------------------------------

Date: Mon, 02 Aug 1999 09:08:44 +1000
From: "Robert O'Connor" <robocon@ozemail.com.au>
Subject: Re :- the Inyx and the Devi Intelligence

Paul Schirf wrote :-
> I like the Inyx.  They're a parasitic lifeform.  "Their original
> hosts were whale sized sea creatures that could generate 
> electrical currents in the same manner as electric eels."

O.K. The original hosts had capacitors made from modified nerve tissue
which could be used to generate electric currents (on discharge).
	So the Inyx led a rather marginal existence siphoning off
power from their original hosts. They would probably be more successful
behaving like Chlamydia, etc. - tapping mitochondria directly for their
energetic needs (although I guess this is difficult if you're
multicellular).
	We could postulate that the Inyx use the electrons they steal (more
likely to be in the form of 'reducing equivalent' cofactors, but this
still requires tapping cell contents) to drive their metabolic
processes. This does *not* free them from requiring other biological
molecules and solvent (of whatever type) to survive - 'building blocks'.

> My question still stands - why are the Devi Intelligence 
> described as pseudo-fungi at all?

My guesses are as follows :-
1. They alternate between a 'spore' and a 'fruiting body' form.
2. They fill the ecological niche of 'reducers' or 'recyclers' - they
close
nutrient loops, processing organic material so that producers can use it
again to make biomolecules.
3. Thay are incapable of exploiting inorganic sources to meet their
metabolic
needs e.g. sunlight, heat or chemical gradients.

Reducing alien ecologies to their simplest elements :-
1. Producers - turn simple compounds into 'biological' ones with the
assistance of external energy sources e.g. green plants and algae.
2. Consumers - eat parts of the producers to meet their metabolic
requirements.
3. Reducers or recyclers - as above.

Robert O'Connor
Medico, Gamer
- --------------------------
In the pipeline :-
* Xenobiology 101 : Looking at the 'minor aliens' in G:T 'Beyond the
Claw' (case studies or 'worked examples')
* Atmospheres : a series on the second UPP digit
- - some stuff on pressure
	- oxygen : why, how, and how much?
- - taints, exotics, etc. : embellishing the classifications
	- some nasty gases for those hell-hole worlds....

------------------------------

Date: Mon, 02 Aug 1999 09:08:51 +1000
From: "Robert O'Connor" <robocon@ozemail.com.au>
Subject: Xenobiology 101 : Ecology, Environment, and Evolution (long)

Ecology is that science that explores how organisms interact with each
other and their environment.

* Introduction
For surface life, factors that determine climate will influence the 
variety of environment types present.
	A key determinant of climate is the amount of energy available
from the primary and the ability of the world to retain some of this
input. The properties of the atmospheric gas mix are important in this
regard. For example, carbon dioxide and methane are well known 
"greenhouse" gases, as they limit the amount of infrared radiation 
reflected into space.
	The presence of life is critical to maintaining atmospheric
composition. The present levels of oxygen in Earth's atmosphere are 
due to photosynthesis. Life with alternate biochemistries using 
gaseous reactants will doubtless affect the atmospheres of their 
worlds in a similar fashion.
	Local differences in the albedo or surface reflectivity of a
planet causes heat gradients to develop in the atmosphere. For 
example, water (oceans) is less reflective than land which is usually
less reflective than clouds.
	These heat gradients, in combination with planetary rotation
(the Coriolis effect), form the basis of weather.
	Solvent (and some nutrient) cycles will have an atmospheric
phase. Vapour will be taken up into warm atmospheric gases, and 
precipitate out as liquid or solid from cold ones - e.g. rain. 
In the case of some nutrients, some living things actively incorporate
compounds into their bodies.
	Three Earthly examples :-
	1. The water cycle. Almost all (over 97%) of water is in the
oceans. Polar ice contains about 2%.
	The balance is in relatively rapid circulation (weeks), in the
form of lakes, rivers, water vapour and rain.	
	2. The nitrogen cycle. Nitrogen is a key constituent of amino
acids and nucleotides, the building blocks of proteins and DNA 
respectively.
	The most important reservoir of nitrogen is the atmosphere. 
Converting gaseous N2 to usable compounds such as nitrates, ammonium 
salts and urea is called 'nitrogen fixation' and is performed 
predominantly by bacteria.
	Most animals and plants maintain a fairly even nitrogen 
balance except during periods of growth (positive nitrogen balance
as protein is deposited) or illness (negative nitrogen balance with
protein breakdown).
	Urea and purines (one of the nitrogen containing bases that
make up the core of nucleotides) are excreted by animals, and recycled
by bacteria.
	3. The carbon cycle. Atmospheric carbon dioxide is the 
'fast compartment'. The CO2 living things 'breathe out' is 
incorporated into glucose by photosynthesis. Significant amounts of
carbon dioxide is dissolved in the oceans (n.b. : gas solubility 
varies inversely with temperature). Carbonate based rocks e.g. 
limestone make up the 'slow compartment'.
	Terrain features influence rainfall. As air masses move over a
mountain range, they cool and water vapour precipitates out. The
formation of deserts may be assisted by the effects of equatorial 
heating - warm, moist air masses move to cooler regions,
and dumps its water. The now dry air masses circulate back towards the
equator, creating dry regions in the mid-latitudes.
	The density of plant life also influences rainfall. Plants
produce water vapour from photosynthesis and vent it into the 
atmosphere (except those plants native to very dry climates) : 
transpiration. Increased humidity, in combination with effects on 
albedo, alter the likelihood of rain.

* Soils
The interaction of geology and weather determines what elements and 
compounds are available for plant life to use. Soils are the 
substrates on which plants grow. They are formed by partly by erosion,
but mainly by the action of living things. Their key
function is to act as a reservoir of solid nutrients (and solvent) 
for plants.   
	Essentially, they vary in moisture content, aeration and 
nutrient content. Areas that enjoy high rainfall or are in the
catchment of run-off from hills, mountains, etc. will obviously have
more moist soils.
	Aeration is a function of both animal and plant activity - 
making the soil increasingly fine grained enhances diffusion of 
oxygen, nitrogen and water into Earthly soils, optimising conidtions
for animal and plant growth.
	Nutrients may be either intrinsic to the soil or washed in
by solvent flows.
	Most soils are complex mixtures of organic and inorganic 
compounds. Their fertility or carrying capacity varies with their 
ability to retain nutrients - or toxic materials e.g. clay soils and
aluminium salts.
	
	On other worlds with more acidic solvents, erosion may be 
greatly accelerated and soils relatively better aerated. However the
latter factor may be offset by the decreased stability of nutrients or
their increased solubility (the only large fertile areas may be where
rivers empty into oceans).
	Differences in local gravity, the presence or absence of plate
tectonics, and atmospheric pressure and constitution will also alter 
the rate and extent of erosion and other geological processes.
 
* Energy flows and food webs
Organisms can be loosely divided on how they obtain the energy they 
need for metabolism.

- - Primary producers obtain energy from 'non-biological' sources e.g. 
sunlight, heat, or chemical gradients (chemosynthetic bacteria in hot 
springs and thermal vents use energy released by oxidation or 
reduction of sulphur compounds).
	They are responsible for making some nutrients available to 
the rest of the community (e.g. CO2 -> carbohydrates ; phosphate -> 
energy containing nucleotides; nitrogen -> nitrate, ammonia -> amino
acids and nucleotides).
	Terrestrial examples : plants and bacteria, green-blue algae,
etc.
	Producers can be further divided into point and area 
subgroups. Point producers are typically single large organisms (trees,
creosote bushes), area producers groups of many small organisms 
(grass, bacteria). This division is a consequence of scaling
laws and niche competition (see below).	
- - Primary consumers eat plants (herbivores) ; secondary, tertiary,
and quaternary consumers (carnivores) eat other consumers. 
- - Decomposers or reducers (e.g. bacteria and fungi) produce simple 
(in)organic compounds that primary producers use again from other dead
organisms. They play an essential role in the cycling of nutrients 
such as nitrogen and phosphorous. 

Food webs are maps that describe how each group of living things 
interacts with each other from a nutritional standpoint.
	There are two broad types :-
	Grazing, where there is enough energy to allow primary 
producers to arise and grazed. 
	Detrital, where the activity of local producers is not 
adequate to supply consumers, so nutrients must be 'imported' e.g.
some soils, the bottom of a pond or ocean, or a cave. 

At each level, energy is consumed in metabolic activity. Each level of
a food pyramid is 10% the size of the level below i.e. 100kg of 
producers (plants, etc.) supports 10kg of primary consumer (herbivore)
supports 1kg of secondary consumer (carnivore), etc.

This 'biomass' relation is universal.
Pyramids based on number of organisms may be partly inverted e.g. in a
forest ecosystem, there are a few large producers (trees) with many
small primary consumers (insects, and other herbivores) and few 
secondary consumers (predators).

* Ecosystems and the Koppen classification system.
(examples kindly provided by Leonard Erickson)
An ecosystem can be defined as a 'spatially explicit unit that 
includes all of the organisms, along with all components of the 
abiotic environment within its boundaries'.
	A synonymous term for ecosystem is biome.

Variation in temperature (available energy) and precipitation ranges
(nutrient flows) are the most important determinants of what types
of biome will appear.
One descriptive system used in geography is the Koppen classification
based on temperature and rainfall.

Koppen classification and example ecosystems
* A : hot, mean monthly temperature > 18 C
Examples :-
Tropical/ dry               Thorn scrub, Savanna
Tropical/ Moderate          Savannah, thorn forest, tropical seasonal
Tropical/ humid             Tropical seasonal or rain forest
Tropical/ wet               Tropical rain forest
Tropical/ very wet          Tropical Rain forest
Tropical/ wetsoil           Tropical swamp forest, mangrove swamp
SubTropical/ Dry            Temperate grassland, Thorn scrub
                            Temperate woodland, Savanna, Thorn forest
SubTropical/ Moderate       Temperate Grassland, Woodland, Forest
                            Thorn forest, Tropical seasonal forest
SubTropical/ humid          Temperate forest, temperate rain forest
                            Tropical seasonal or rain forest
SubTropical/ Wet            Tropical rain forest
SubTropical/ Wet Soil       Temperate Swamp forest,
                            Tropical swamp forest, Mangrove swamp

* B : dry (average rainfall less than 300mm/yr)
Variants : h (average temp > 18 C) or k (average temp < 18 C)
Examples :-
Tropical/ Arid              Barrens, Tropical desert
SubTropical/ Arid           Barrens, Warm temperate desert,tropical
                       	    desert
Warm Temperate/Arid         Barrens, Warm Temperate desert, semidesert
Cold Temperate/ Arid        Barrens, Semidesert scrub,
                            Temperate shrub, Taiga

* C : temperate, mean temperature of coldest month -3 to 18 C
Examples :-
Warm Temperate/dry          Temperate shrub, temperate grass,
                       	    Temperate woodland
Warm Temperate/Moderate     Temperate Forest (Deciduous or evergreen)
Warm Temperate/Humid        Temperate Rain forest
Warm Temperate/Wet soil     Marsh,  Temperate Swamp forest
			    Temperate shrub, Thorn scrub

* D : cool, mean temperature of coldest month < -3 C
Examples :-
Cold Temperate/ Dry         Taiga
Cold Temperate/moderate     Taiga, Elfin woodland
Cold Temperate/Wet Soil     Bog.

* E : cold climates, mean temp of hottest month < 10 C
Variant : H > 1500m above sea level
Examples :-
Arctic-Alpine/ Arid         Barrens, Arctic-alpine desert, Tundra
Arctic-alpine/ Dry          Tundra, Arctic-alpine desert
Arctic-alpine/ wetsoil      Tundra, Bog
Polar/ Arid                 Barrens

To this list we can add the following aquatic biomes :-
Rivers
Lakes and ponds
Estuarine & marine mudflat: Coastal shallows
Sandy Littoral              Ocean Beaches
Rocky Littoral              Marine cliffsides
Marine coastal              Ocean floor, lighted. Kelp beds and coral
                            reefs
Marine Benthic              Ocean floor, dark zone
Marine Pelagic              Open sea. (further divided into lighted 
			    zone, dark zone, and near-bottom).

Two other biomes that have been recently discovered are geothermal 
(deep ocean vents, hot springs) and deep rock (e.g. bacteria found in
oil fields and even deeper porous rocks). As noted in the first post,
subsurface microscopic life exploiting chemical and thermal gradients
for energy may constitute much of a world's biomass.

Another less obvious biome is the environment occupied by the "aerial
plankton" - bacteria, etc. that waft about in the air around us,
massing 0.1 grams or less.
	On other worlds with lower gravity or chemistry and 
temperature favouring aerostatic flight, the atmosphere might look 
more like the sea, with jellyfish-like 'floaters' competing with 
bird-like creatures for prey... a common motif for life
in gas giant atmospheres in science fiction.

So in general terms, ecosystems vary in the energy and solvent 
available to them, which influences the amount of life they can 
support. Life's presence helps maintain conditions that the ecosystem
continues to florish. In time, however, the effect of life on an area
may cause conditions to change, favouring different organisms.
	This process is called succession and will be discussed in a 
later section.

* Niches, habitats and species interactions
(with assistance from Leonard Erickson and Ian Ferguson)
A 'niche' can be defined as 'the functional role of an organism 
within its community'.
Niches are well described in the various Traveller rules (e.g. 
scavenger, hijacker, omnivore, etc.)
	In general terms, habitats can be divided into the following 
areas :- aquatic, land and air. Most organisms span across two or 
more of these.
  	e.g.	mud (bacteria or worms in the lake's bottom)
                liquid (algae, snails, crayfish, fish)
                soil (earthworms, fungi)
                gas (deer, bats, bryophytes)
                mud/liquid (sea-weed, clams)
                soil/gas (trees, gophers)
                liquid/gas (whales, waterstriders, ducks)
                liquid/gas/soil (beaver)

	Adaptations to a given habitat are driven by remorseless 
evolutionary pressure, based on the relevant physical laws that govern
it.
	The fish that can swim faster will escape a predator ; its 
progressively more streamlined descendants will eventually dominate 
the watery niche in which it lives.
	So traits that assist survival are passed on (though sometimes
'bad' genes hitch-hike on the 'good' ones).
	
Species interactions result from the interaction of niches and the 
food web.

Types include :-
- -Predation :- plant is eaten by herbivore is eaten by carnivore.
- -Competition :- use of similar resources - e.g. herbivores in a given 
ecosystem
- -Allelopathy :- inhibition of competitors e.g. fungi and bacteria 
making antibiotics, pine trees acidifying the soil around them.
- -Parasitism :- dependence of one organism upon another (the latter 
may or may not benefit from the association). E.g. tapeworm and man
(amensalism) or remora and shark (commensalism).
- -Protocooperation :- a mutually beneficial but non-obligate
relationship e.g. goby fish and pygmy shrimp (the latter digs a 
burrow for the former who catches the food).
- - Mutualism :- symbiosis : mutual benefit, mutual dependence 
(lichens are communities of algae and fungi).
 
* Evolution and succession
Charles Darwin's 'The Origin of Species' is one of the most important
works in all science. In that book, the theory of evolution was first
brought to the attention of a wider audience.
	Drawing from observations made over many years as a naturalist,
Darwin proposed that organisms were in a continual struggle to secure
their place in a given environment. 'Natural selection' is the term he
used to describe this process and its consequences.
	As mentioned above, natural selection is based upon the 
gradual accumulation of improvements.
	Consider flight as an example. There are many theories as to
how flight began. Given the long history of life on Earth, it was
probably discovered independently several times throughout the 
animal kingdom.
	Wings may have begun as radiators for insects ; as the insects
grew larger over evolutionary time, their radiators grew too - 
eventually attaining a critical wingspan. Halteres or wing stubs still
persist on flies, but act as control surfaces during flight.
	Vertebrates variously sport wings that are modified arms or 
forepaws, gliding membranes between fore and hind limbs and even 
modified ribs. Leaping from tree to tree, or making running jumps
from the ground to flee or catch prey are logical starting points for
the development of flight.
	Lastly there are the cephalopods - octopi and squid can 
forcibly empty their swim bladders to effect 'jet propulsion'. There
is at least one species of flying squid.
	Vision has a similar history of many independent starts 
(at least forty times). Across the animal kingdom a vast
range of visual systems, from clumps of light-sensitive skin cells
to sophisticated camera and compound eyes can be seen.
	Interestingly, the genes that code for overall eye development are
tightly conserved across species ; there is not very much difference
between those of a fruit fly, mouse or man.

Succession can be seen as a form of ecosystem evolution.
Changes in the environment are brought about by a progression of plant
communities and the  formation of increasingly nutrient-rich soils. 
	E.g. on a sand dune, the bare sand of the beach gives way to
dune grass, then perennial herbs, shrubs, light-loving and 
drought-tolerant trees, and finally shade-tolerant trees that require
moderate to high soil moisture.

There are two types of succession. 
	Primary succession begins with bare rock, sand, or mineral 
soil. Examples are sand dunes or a volcanic blast zone. 
	In secondary succession, nutrient rich soil is already 
present; because of this, changes in plant communities are more rapid 
and are driven by the availability of light and water. An example 
would be an old field becoming forest. 

Sucesssion can be divided into three stages :- pioneer, intermediate
and climax.
	In the pioneer stage, diversity of species is low as the 
supporting plants are small and sparse.
	Over the course of years, species diversity expands greatly as
more plants arise ; this intermediate stage is the 'richest' one in
terms of diversity and plant density.
	In the climax stage, the environment has matured. Trees 
dominate and support a wide range of animal life.

Robert O'Connor
Medico, Gamer

------------------------------

End of Traveller-digest V1999 #911
**********************************

To unsubscribe to Traveller-Digest, send the command:

unsubscribe traveller-digest

in the body of a message to "traveller-request@lists.imagiconline.com".
If you want to subscribe something other than the account the mail is
coming from, such as a local redistribution list, then append that
address to the "subscribe" command; for example, to subscribe
"local-traveller":

subscribe traveller-digest local-traveller@your.domain.net

A non-digest (direct mail) version of this list is also available; to
subscribe to that instead, replace all instances of "traveller-digest"
in the commands above with "traveller".

Multi-Player Games Network http://www.mpgn.com
