Animals in any ecological system interact with each other, forming food chains, obeying instincts, defending territory, and generally living out their lives. When men enter such an ecological system, they will encounter the animals of the system, prompting natural reactions, such as attack or flight....Although the precise nature of animals may change, and they may prove quite alien to ordinary experience, most will conform to the broad classifications given below. A referee may choose to establish his own ecological system on a specific world, ignoring the encounter system outlined here. This system, however, is intended to allow broad latitude in both animal types and attack/defense mechanisms, while remaining essentially logical and reasonable.
Worlds and Adventures, pg. 24
Traveller, 1977 Edition
What's unfortunate about the original Traveller Animal Encounters section was that we ignored it so thoroughly back in 1977. This is incredibly unfortunate, since it is in this section that there were some amazing opportunities for world-building, all too often treated as "wandering monster" checks. But that's not what the Animal Encounters section is about - it is actually a fairly streamlined system for devising creatures and developing their places in an ecology, without going into so much depth as to bog things down.
I do not recall in 1977 or 1978 any major attempt among Traveller players in the Twin Cities to come up with ecologies and creatures for their campaigns (I freely admit I might be misremembering). We were so busy trying to replicate the Dorsai, or the Polesotechnic League, or some other space opera, that we simply didn't appreciate what was there in the rules. And here is the crux of the problem: just how much imagination do most referees have, when they need to create difference ecologies, world after world after world? Most of the referees I knew simply didn't get into this level of detail, and so we avoided it altogether. Looking at them now, not only do I find myself wanting to engage in world-building, but to take some time and really work out some of the creatures that might be encountered once player-characters make landfall.
Possibly one of the most interesting aspects of the animal encounter generation system is how easily it could be adapted to generating aliens. Humans are originally omnivorous brachiating hunter stock, roughly 60-75 kilos. It would be fascinating as a creative exercise to generate the precursors of alien races and see what you come up with, especially if combined with the extended star system generation system from Book 6, Scouts. What this illustrates is just how easy it is to add depth to the entire Traveller "mechanic" framework - this is true throughout the various sub-systems of the rules: character generation, ship design, star systems, etc. But it also illustrates the enormity of the tasks involved in creating a truly in-depth universe. The original admonition to generate a sub-sector and see what that gives you is almost precisely the same as admonitions in AD&D to start small when building your own world - a barony, with some nearby places of adventure, for example.
Next time is the last section of the 1977 Edition Traveller rules: Psionics. After that, I intend to look at some of the early supplements and additional material, and how they changed the game. What I am hoping to do is see what Traveller was like, pre-Third Imperium. There was a tremendous opportunity available at the time to come up with multiple settings for the game, rather than the focus on that single campaign world, magnificent and yet flawed at the same time. Judging by the TML debates about Aslan females wearing comfortable shoes while serving aboard pirate vessels that are tracking near-C rocks being flung at planets, there's been a tremendous amount of energy expended on the Third Imperium - and too much of it woolgathering.