Shrog

Shrogs are various intelligent tamjacks descended from the seashrog, distinguished from their relatives by their larger brains, capacity for tool use, and the presence of bone cores within their scale armor and other ornamentation. They are a type of shrew.

Anatomy
Shrogs have typical external anatomy for tamjacks, apart from the sometimes-obvious enlarged braincase and seemingly lower ear position. Their thumbs are opposable, though designed for holding things rather than climbing, distinguishing them from the hands of primates. They have heterodont dentition which includes incisors, canines, premolars, and molars.

Shrogs are typically facultative bipeds. When unladen with tools or other handhelds, they will walk or run on all fours, but when their forelimbs are occupied they can easily move about on three legs or even just two. They are also generally capable of standing upright on their hind legs for short periods of time.

Like other tamjacks, shrogs are placental but retain a pouch. Gestation typically lasts multiple months and it can take years for a shrog to reach full size. Unlike other tamjacks, by default, male shrogs have a pouch as well, which serves as a protective sheath for their genitalia. Most shrogs mate belly-to-belly due to the spikes on their backs and tails making mounting difficult or risky. Like other tamjacks, shrogs have internal testes; in combination with males placing their genitalia inside their pouch, this can make it difficult to distinguish males and females on sight alone in most species.

Shrogs have typical internal anatomy for terrestrial spondylozoans. They have red iron-based blood, a pair of lungs in their chest, nostrils at the end of their snout, and six eyes. The anus and reproductive opening are located at their back end, between their legs and under their tail.

Behavior
Shrogs are generally fairly behaviorally complex. Their high intelligence makes them very adaptable and even capable of inventive behavior.

Social Behavior
Different species of shrog have differing social behavior. Some species are only social when mating, while others live in large groups and are comfortable in close quarters. In general, as a result of their less-social starting point, even very social species will prefer separate and even disparately-placed nests, though there are exceptions. One major contributing factor to this is the lack of a hierarchy instinct by default, which makes an organized social structure difficult to maintain.

Parental Care
By default, shrogs provide parental care, like most other shrews. This includes feeding and protection. By default, shrogs form mated pairs and both parents contribute to raising their babies, but in some more solitary species the father plays no part.

Intelligence
Shrogs are significantly more intelligent than most species on Sagan 4. They demonstrate self-awareness and the ability to craft and use tools for hunting or defense. However, their social intelligence is comparatively very low. Like many intelligent animals on Earth such as apes and crows, shrogs are aware of their knowledge and intelligence to some extent, though their lower affinity for social interaction makes the spread of new ideas slow and difficult except in especially social species.

Though often compared to great apes in intellect, shrogs do not behave in a particularly ape-like manner. In social species, rivalry between social groups is generally minimal; they do not go to “war” like chimpanzees, and even the most violent encounters rarely result in serious injury or death. If there is any Terran ape that shrogs could actually be compared to at all, it might be the orangutan, which is similarly not very social but has a very high affinity for tool use. Notably, by default, shrogs are actually more social than orangutans.

Contrary to popular belief, shrogs are not actually particularly close to achieving personhood. Their affinity for tool use is unusually high when compared to, say, most Terran mammals, but this is partly a continuation of the already-advanced abilities of their less intelligent ancestors. Indeed, the most technologically advanced nest built by a shrew doesn’t even belong to a shrog at all, but to the unrelated pickaxe tamow.

Vocalization
Shrogs are vocal and can make a variety of sounds, though most of their calls are instinctive. An exception is their “name-barks”, which are a modified form of the instinctive “attention bark” using inflections to call out to individuals. Some social species such as the Maineiac rivershrog have modified “name-barking” into a rudimentary language.

Tool Use
Shrogs are famous for their tool use, which includes the construction of spears used for hunting and defense. Dexterity varies somewhat between species, as does the types of tools used, though spears are almost completely universal.

Shrogs have somewhat of an effect on their environment as a result of cutting down trees for tool and nest construction, however they are not overly destructive. Unlike human logging operations, which can devastate ecosystems, the influence of shrogs on floral communities can actually be beneficial. The breaks they create in canopies can facilitate new growth, and the waste left behind becomes food to important decomposers and detritivores.

Nest Construction
Shrogs construct some of the most structurally complicated nests of any shrew. The nests are typically radially symmetric, supported by logs arranged in a radiating pattern and bent into rib-like arches.

Notably, the famous nest construction capabilities of shrogs are not entirely a result of their intellect, but an elaboration on instinctive behavior. Though the nest of a shrog which was hand-raised in captivity will certainly differ in appearance from one built by wild shrogs, the basic radial dome or bowl shape is largely maintained.

Evolution
All shrogs evolved from the seashrog, which first appeared in the middle Bonoian. While its direct ancestor, the tamjack, had originally evolved in an archipelago where landfall was frequent, rising sea levels and shifting tectonic plates had turned that archipelago into a stretch of deep, open sea, which had made flora too infrequent to sustain an herbivore. The seashrog evolved to replace its ancestor, gaining higher intelligence, omnivory, and tool use to assist it in surviving in the harsher environment.

Unusual among creatures this intelligent, the seashrog was immediately set for speciation, having made landfall on every single landmass on Sagan IV. This resulted in an immediate radiation into new inland species all over the planet.

Size and Diversity
With a few exceptions, shrogs are typically medium-sized creatures which can be described as roughly “man-sized”. Their reliance on their intelligence puts somewhat of a limit on how small they can be. However, with their ridiculously broad range, variants much larger or smaller than the majority easily exist. The largest shrog is the shrogre, which is also the largest of all shrews.