Boreal Grasslands of Northern Loxodia

An interesting and entirely coincidental feature of Apterra is that each of its three major continents has two mountain ranges. Ailuropia in the west has a pair of long, straight chains, separated by a wide, dry basin. Abeli, the birthplace of life on Apterra, has a massive, winding ridge dominating its western half, while in the southeast there is an older, smaller range. Meanwhile, the two-lobed continent of Loxodia has a wide, hooked series of peaks that follows the coast, then turns southward to surround the Loxodian interior desert. Similar to Abeli, this continent also has a minor mountain range tucked away in its temperate zone. On the slopes of these hills, a unique biome is emerging.

Save for the tropics, this area currently boasts the planet’s highest plant diversity. Eighteen varieties of buffalograss descendants live here. Genetically, all of these are still incredibly similar, retaining the capacity to hybridize and produce fertile offspring. However, this is prevented by various prezygotic and postzygotic reproductive barriers. These include the timing of pollen production - two plant populations can’t mix their genes if they never reproduce at the same time. More importantly, though, hybrids have a marked tendency to fare poorly in their environment, not due to any genetic defect, but simply as a result of being less well-adapted to that ecosystem than either of their parent species. In this way, even in the instances where hybrids are produced, they are just as quickly weeded out of the gene pool by natural selection.

Of course, in a world so abundant in available niches, more than a few hybrids are bound to find a place in their environment where they can succeed. When this happens, the hybrid plant may become the founder of an entirely new species. As Apterra develops, the number of different native grasses is bound to increase exponentially - and equally will all the other lineages diversify - but at the moment, a few dozen forms are the most that we can reasonably expect to find in any one place.

And in this place, the cold, wet forests of the north Loxodian mountains, strange things are already happening to the local flora. A mutation has occurred, similar to the one that produced the tall grasses of the tropical wetlands, but with a very different effect. Instead of increasing the length of the stalk, the individual blades of grass have become massive, often exceeding a meter in height. They form a rosette around the short stem of the plant, creating a basket-like shape. A dwarf cousin of this plant has a similar structure, but its leaves are shorter and broader, forming a cup structure measuring less than 20 cm in height.

Lichens coat the bare rock faces on the steeper slopes. At the base of these cliffs, where the ground is mostly protected from the harsh winds that blow across the rest of the landscape, lives a delicate grass with a unique trick. Growing from the thin strip of soil directly under the sheer rocks, it leans against the edge of the mountain. At every node, a series of roots clings to the slope, holding the vine steady as it ascends up to four meters from the earth below.

At the very peaks, where the winds reach a gale force on a daily basis, only one type of grass can withstand the elements. Its leaves are short, folded lengthwise into a conical shape that resists bending, and situated low to the ground. On spring afternoons, when the winds reach their yearly maximum, clouds of pollen roll off the mountaintops. The hope of each plant is that their genes will be carried to the next peak, producing a new generation of high-altitude grasses.

The densest regions are the valleys below each mountain, where the winds are calmer and warmer, creekbeds run with water year-round, and rats spread the seeds of every plant far and wide. Short, thick beds of grass line the riverbanks, living in the shadows of taller forms with sharp, pointed blades that deter the grazing rats of the area. On the other hand, the most common of all local grasses is one that uses the rats to its advantage. Once per year, it produces a tremendous crop of seeds, far exceeding what the rodent population can consume. In response, the rats take this abundant food source into their underground nests. In the event that a grain stockpile is forgotten - or if its owner dies - these seeds sprout when the autumn rains arrive, completing the cycle. In this way, the grasses bolster the population of their own disperser, leading to ever-increasing reproductive success for both groups.

If we peer into the brooks that weave their way through this land, several forms of Gambusia reveal themselves. Already a small fish, one branch of these minnows has shrunk further, attaining a size of no more than a centimeter in length (and smaller still for the males). This lifestyle is a successful one, as massive shoals swim through every meter of the region’s waterways. A specialized algivore group also lives here. They are less visible, as they stick close to the submerged rocks where their food grows. A dark mottled green color keeps them hidden from intrepid fishing rats, a rodent clade rapidly becoming distinct from its granivorous cousins. 

Apterra’s current world record holder for "largest fish" a fifteen-centimeter-long form that dwells in fast-moving rapids across this region. While its cousins would be battered against the sharp rocks lining the beds of these streams, these silvery-gray mega-minnows alone have the muscle power to dodge the many obstacles in their habitat. They, too, have a diet primarily consisting of algae. However, in the event they are swept into calmer waters, they are more than happy to prey on the young of smaller Gambusia before returning to their preferred environment.