Driftwood Islands

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The Driftwood Islands are a massive collection of raft-building cone puffgrass colonies which formed in a large ocean gyre in Jujubee Ocean. It was able to get so massive because the ocean currents would push driftwood in but never remove it, only slowly rotate and shear it. Many islands within the gyre are as big as 20 kilometers wide and 300 meters thick. The east and west ends of this "archipelago" have some islands as wide as 50 kilometers. The founding colonies consist not only of driftwood, but also of incorporated seashrog and marine tamow nests. Soil formation has occurred on all large colonies, and they can support larger flora and fauna as a result, making these islands into a set of biomes in their own right. Due to their position, the southern half of the Driftwood Islands are fairly dry but not quite desert-like, the inland conditions being like a terrestrial chaparral biome while the edges are more like temperate beaches. The northern half, meanwhile, is wetter and more forest-like.

The islands are organized into east, west, and circulating islands. The eastern and western islands are larger and more stable, generally staying in the same place indefinitely. The circulating islands are smaller and move between either end of the main gyre, and they collide and break apart more often. Species exclusive to just one of these are restricted to rapidly-speciating genera, such as minikruggs, which speciate so fast that they would already have produced a new species by the time they’re transported to the other side; everything else is transported between the two ends too often for anything to be exclusive to just one. Islands get thicker as a result of collisions; they can thicken as a result of being compressed, and it is not uncommon for one island to be "subducted" under another. Vertical mass is also accumulated through deceased sky organisms falling down onto the islands.

Mature floating islands consist of several layers. The bottom-most layer, which can hang deep enough to brush the boundary between the sunlight and twilight zones, is made of a mud-like sludge created by the decomposition of higher layers. Further upwards, this transitions into a thick layer of muddy soil and occasionally the remains of the island’s founders, saturated with seawater. This layer is almost completely devoid of oxygen, though it may contain significant pockets of methane produced by anaerobic microbes. These methane pockets play a significant role in keeping the island afloat. Above the water level is more soil and increasingly intact floral remains, as well as more oxygen, until one reaches the sunlit surface which is covered in grass. When standing on the surface of a large, mature island, it is nearly indistinguishable from a land biome except in the absence of stone--though biogenic silica makes its way into the island’s makeup through silicon-using phytoplankton, and fragments of bone and shell can be found in every layer, the Driftwood Islands contain no true rocks unless some are brought to them artificially.

Insular dwarfism and gigantism apply freely on the driftwood islands.

Biomes Created

Map of Driftwood Islands. Note that the driftwood islands' biomes are not solid masses, but collections of many floating islands. Broken up shapes represent decreasing frequency of the islands in certain parts of the gyre, while the two circles in the east and west contain the largest and most stable islands.

The Driftwood Islands form several unique biomes. In most of them, any species present must have some method of island-hopping.

The main surface biomes at the time of formation are dominated by grass and dotted with clumps of trees and bushes, though this is likely to change as more flora and fauna come to inhabit them. Moisture-wise, they consist of a chaparral-like biome (Driftwood Islands Chaparral, temperate + mixed) dominating most of the southern half of the landmark, temperate woodland (Driftwood Islands Temperate Woodland) in the southeast, and tropical woodland (Driftwood Islands Tropical Woodland) spanning the entire northern half. Despite being classed as woodland, however, the constant shifting means that actual forest-like growth is rare. Any flora present inland must be in all of these biomes or be able to go dormant or enter a dormant generation when conditions change, due to the islands shifting constantly.

The next new biome is the Driftwood Islands Underbelly. This is the underside of the islands, consisting of murky water and an all-you-can-eat buffet of detritus. It is a completely unique biome which is considered to be part of the twilight zone. No light reaches the underbelly, and any species which lives on the underbelly must have some ability to spread between islands. Their type and flavor are Ocean + Unique.

The third new biome is the Driftwood Islands Bank. This is considered both a beach and a salt marsh/swamp, as it has features of both. It is a muddy biome lapped by salty ocean waves. Their type and flavor are Temperate + Beach/Wetlands for the southern half of the landmark, and Tropical + Beach/Wetlands for the northern half.

The fourth new biome is the Driftwood Islands Shallows. The Driftwood Islands Shallows are parts of a given island which are submerged and connected to the open ocean, and they are classified as shallows. Rather than sand, the floor is made of mud. Any species which live here must have some way to move between islands. Their type and flavor are Temperate + Shallows in the south and Tropical + Shallows in the north.

The fifth new biome is the Driftwood Island Lakes. These are isolated bodies of water which form “inland” where part of a given island dips below the sea level. This usually occurs as a result of islands getting thinner from being pulled apart or from natural lowlands sinking as they grow larger. They are saltwater and usually have nothing living in them when they form. They are classified as temperate salt lakes. Any species which live here must have some way of traveling between lakes. Their type and flavor are Temperate + Salt Lake in the south and Tropical + Salt Lake in the north.

The sixth new biome is the Driftwood Islands Water Table. It consists entirely of mud and detritus, and is summed up as subterranean wetlands. This connects directly to the lakes and the bank, and it is almost completely devoid of oxygen. As there is no rock in the Driftwood Islands, no caverns are formed, so only microbes, decomposers which can grow through the mud, and very small burrowing fauna may reside here. This biome is home to Seacleaners and may contain massive pockets of methane. All species in this biome must have some way of moving between islands. Their type and flavor are Subterranean + Wetlands.

Founding Biota

In addition to various global genus groups, the Driftwood Islands supported the following species when they formed:

The following species colonized the islands as a result of shrog activity and various nests being incorporated:


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