Battering Helmethead 

A crested thorngrazer that favors fight over flight, male battering helmetheads battle over mating rights while related species prefer to sing and dance.

The battering helmethead is a crested thorngrazer of the upland plain. A close relative of the more numerous rumbling helmethead, or rumblers, these batterers are only half as large but much more pugilistic, always ready for a fight. They make their home on drier lands above the soglands, feeding mainly on ground vegetation, and here can be found in smaller aggregations of just a few tens to sometimes one hundred animals. Social groups are similar to their relatives with female herds and loosely associated roaming males, but the males of this species are even less tolerant of each other. Batterer males fight one another head to head to demonstrate strength and dominance directly, in stark contrast to the flamboyant rumblers, which rely mostly on display. 

Though they share a common ancestor just 2.5 million years ago which already had the precursors to the rumbler's specialized amplifying crests, in the battering helmethead most of this once hollow space has now been filled with a thick, solid shield of bone ringed externally by horn-like teeth as an adaptation to this more violent physical confrontation. Males butt heads with tremendous force, like rams, and fights between equally matched opponents may last an entire day until at last one collapses or turns and runs. While very closely related to their sister species, hybridization does not occur within this genus, as each species is so very different from the others in courting behavior and mate selection that there is no overlap of social behavior to lead to mating. If hybrids ever did exist, they would be highly dysfunctional and prone to injury, having weaker skulls than necessary to fight while also being unable to win a mate with an impressive display. In crested thorngrazers, hybridization is rare and usually detrimental.

Being prone to reproductive isolation through behavioral shift means that these animals can rapidly become distinct species and fill different niches. Stocky and small, battering helmetheads can climb higher terrain that rumblers cannot manage, and can often be found grazing volcanic hillsides other thorngrazers would not be able to reach. Here, in contrast to lowlands, short shrubs and occasional trees may be found, for the mouth of the batterer is smaller and narrower than most other thorngrazers and less suited to crop plants at the root; instead, it usually feeds just under its head height, trimming only the tops off of woody plants and so not necessarily causing their death. This thorngrazer, while aggressive and able to defend itself againstsome enemies, is still small enough to have many predators, and more intelligent carnivores such as larger foxtrotters that can easily climb up these slopes and plot ways to avoid their defenses keep them on the move, further preventing the total stripping of the landscape. On flat terrain they are occasionally hunted by sawjaws, but by far their most pressing threat comes from huge, flying predators, against which their best chance of survival is simply to run, also ensuring that they don't spend too long grazing in one place.

Though much of the snout of the battering helmethead is now solid, the nostrils of adult males still open very high on the head, above and behind the eye sockets, and so a resonating chamber remains on both sides of the bony shield, albeit smaller than those of their relative. This allows batterers to still produce distinctive calls, but these are of a much higher pitch than their relative due to the narrow diameter of the chamber. Female herds of this species are noisy, bringing to mind a chorus of whistles as they communicate, while males produce short, single-note trumpet-like vocalizations to advertise claim of their harems.