Well it is, in a large region. It didn't in a pocket region, that was why I asked. I wonder what is going on here.
Should I post it on bug tracking?
This came from a favorite world of mine, with the following populations.
130963 Dwarves
66407 Humans
141128 Elves
156821 Goblins
2441 Kobolds
Total: 497760
Created in DF v0.34.05.
[WORLD_GEN]
[TITLE:LARGE REGION]
[SEED:iyeAcSaQm4qm08G8yusa]
[HISTORY_SEED:ikEOemWC2mUGsoCk6yoY]
[NAME_SEED:Sk2kk6yM2keKgK2ikKem]
[CREATURE_SEED:MAacEO2KGqCcEYi08oss]
[DIM:257:257]
[EMBARK_POINTS:1274]
[END_YEAR:1050]
[BEAST_END_YEAR:300:80]
[REVEAL_ALL_HISTORY:1]
[CULL_HISTORICAL_FIGURES:1]
[ELEVATION:1:400:800:800]
[RAINFALL:0:100:400:400]
[TEMPERATURE:25:75:400:400]
[DRAINAGE:0:100:400:400]
[VOLCANISM:0:100:400:400]
[SAVAGERY:0:100:400:400]
[ELEVATION_FREQUENCY:1:1:1:1:1:1]
[RAIN_FREQUENCY:1:1:1:1:1:1]
[DRAINAGE_FREQUENCY:1:1:1:1:1:1]
[TEMPERATURE_FREQUENCY:1:1:1:1:1:1]
[SAVAGERY_FREQUENCY:1:1:1:1:1:1]
[VOLCANISM_FREQUENCY:1:1:1:1:1:1]
[MINERAL_SCARCITY:2500]
[MEGABEAST_CAP:75]
[SEMIMEGABEAST_CAP:150]
[TITAN_NUMBER:33]
[TITAN_ATTACK_TRIGGER:80:0:100000]
[DEMON_NUMBER:52]
[NIGHT_TROLL_NUMBER:26]
[BOGEYMAN_NUMBER:26]
[VAMPIRE_NUMBER:26]
[WEREBEAST_NUMBER:26]
[SECRET_NUMBER:52]
[REGIONAL_INTERACTION_NUMBER:52]
[DISTURBANCE_INTERACTION_NUMBER:52]
[EVIL_CLOUD_NUMBER:26]
[EVIL_RAIN_NUMBER:26]
[GOOD_SQ_COUNTS:100:1000:2000]
[EVIL_SQ_COUNTS:100:1000:2000]
[PEAK_NUMBER_MIN:50]
[PARTIAL_OCEAN_EDGE_MIN:2]
[COMPLETE_OCEAN_EDGE_MIN:0]
[VOLCANO_MIN:15]
[REGION_COUNTS:SWAMP:1032:7:6]
[REGION_COUNTS:DESERT:1032:7:6]
[REGION_COUNTS:FOREST:4128:13:12]
[REGION_COUNTS:MOUNTAINS:8256:9:9]
[REGION_COUNTS:OCEAN:8256:7:6]
[REGION_COUNTS:GLACIER:0:0:0]
[REGION_COUNTS:TUNDRA:0:0:0]
[REGION_COUNTS:GRASSLAND:8256:13:12]
[REGION_COUNTS:HILLS:8256:13:12]
[EROSION_CYCLE_COUNT:250]
[RIVER_MINS:400:400]
[PERIODICALLY_ERODE_EXTREMES:1]
[OROGRAPHIC_PRECIPITATION:1]
[SUBREGION_MAX:2750]
[CAVERN_LAYER_COUNT:3]
[CAVERN_LAYER_OPENNESS_MIN:0]
[CAVERN_LAYER_OPENNESS_MAX:100]
[CAVERN_LAYER_PASSAGE_DENSITY_MIN:0]
[CAVERN_LAYER_PASSAGE_DENSITY_MAX:100]
[CAVERN_LAYER_WATER_MIN:0]
[CAVERN_LAYER_WATER_MAX:100]
[HAVE_BOTTOM_LAYER_1:1]
[HAVE_BOTTOM_LAYER_2:1]
[LEVELS_ABOVE_GROUND:15]
[LEVELS_ABOVE_LAYER_1:5]
[LEVELS_ABOVE_LAYER_2:1]
[LEVELS_ABOVE_LAYER_3:1]
[LEVELS_ABOVE_LAYER_4:1]
[LEVELS_ABOVE_LAYER_5:2]
[LEVELS_AT_BOTTOM:1]
[CAVE_MIN_SIZE:5]
[CAVE_MAX_SIZE:25]
[MOUNTAIN_CAVE_MIN:100]
[NON_MOUNTAIN_CAVE_MIN:200]
[ALL_CAVES_VISIBLE:0]
[SHOW_EMBARK_TUNNEL:2]
[TOTAL_CIV_NUMBER:40]
[TOTAL_CIV_POPULATION:15000]
[SITE_CAP:1500]
[PLAYABLE_CIVILIZATION_REQUIRED:1]
[ELEVATION_RANGES:8256:16512:8256]
[RAIN_RANGES:8256:16512:8256]
[DRAINAGE_RANGES:8256:16512:8256]
[SAVAGERY_RANGES:8256:16512:8256]
[VOLCANISM_RANGES:8256:16512:8256]
I tried to reproduce the world from that, and what I got was one with these populations.
151251 Dwarves
76379 Humans
143451 Elves
236856 Goblins
2301 Kobolds
Total: 610238
But I had re-titled it as PLANE OF SOULS, so I tried changing that back to LARGE REGION. What I got was:
142325 Dwarves
63612 Humans
141294 Elves
202481 Goblins
2355 Kobolds
Total: 552067
Which isn't either of the above, but the one entitled PLANE OF SOULS did generate the same world twice.