This is the one group that is specific only to the Metazoic.
They also dominate the Metazoic era with their grace and unique beauty. This group is descended from elephant shrews. The
group is comprised of mammals that have complex and varied lifestyles, from tiny grass eaters to the
largest predatory mammals ever to evolve on land. They range in size from the tiny Dendromillops to
the giant Cervilecticula. All species have hooves, like modern ungulates, of one kind or another. All have
long legs and are great runners. The appearance varies, Dendromillops somewhat resembles the
modern elephant shrews, but lives in the trees. The deinognathids are quite a largely varied group as well.
Some species are deer-like, while others are bipedal, kangaroo-like animals. But all deinognathids are
carnivorous. One species, Feresetta, is a small and very light-weight deinognathid with elongate toes
like modern jacanas. They also gave rise to the family of other small, jacana-like mammals, the lily-walkers.
The entire group, Trelatebrata, is made up of 4 superfamilies:
Therapedoidea (contains the families Therapedidae, Cerosidae, Choerocaballidae,
Immanidae,
Aquatragulidae and Pasceridae)
Deinognathoidea (contains the families Deinognathidae, Jacanatheriidae, and
Pelargidae)
Megacolloidea (contains the families Megacollidae and Diplonearidae)
Ungulascelidoidea (contains the family Ungulascelididae)
Most species are large, but as stated before, there are some small and delicate
species. The trelatebrates are so named because both males and females have 3 vents, and no
external testes. The reproductive tract is separate from the urinary tract as females only come into
estrous one day out of the year, and there is no chance of the valuable sperm being lost, killed or voided
in the urinary tract. In the Deinognathoids the teeth are serrated and actually peg-shaped. In the large species,
like Deinognathus, the teeth are made for crushing, not necessarily tearing, though they are quite
effective at tearing off chunks of meat. In the omnivorous species, as those in the Therapedoidea, the
jaws are powerful, but the teeth are flat and made for grinding vegetation, with sharp incisors for
ripping. The tail is long and thick and used to counterbalance the head, and also to help the animal keep it's
balance when running, particularly for the bipeds.
Another Branch in the Family Tree
There is another branch in the Metazoic family tree left by
the elephant shrews that is distantly related to the therapeds. They are not within the order Trelatebrata, but represent their own
orders. They are groups of mammals known by the collective name "sinecrus". These animals also
descended from elephant shrews, but took a very different turn from the trelatebrates. They take the place of
cetaceans in many cases. Most are present in the Pacific Ocean, and Batavia. The Batavian Islands seem to be
the home point for sinecrus. They inhabit all wetland habitats, from the surrounding ocean to
small lakes and streams. On the islands themselves, there are 3 varieties, there is a horned variety with tusks
that extend through the snout, a carnivorous variety that lives like modern crocodiles, and a vegetarian
variety that lives like modern manatees. All have long foreflippers and the hind legs are reduced to tiny
sized flippers that are virtually useless. The tail swings side-to-side as in fish, rather than up and down like
whales. Most are small to medium sized creatures, the largest sinecru on the Batavian Islands measures 10
feet in length. The sinecrus that live in the ocean it's self can get considerably bigger, some as
big as 22 feet long.
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