yeah, so I’ve got quite a few of them that I’ve accumulated over the years. I still need to throw a character page up so people can have an idea of who/what they are…
they do not all exist in the same universe (or at least, these versions of them don’t). Sam, Ike, Terry, and Mira all exist in a sci-fantasy dystopia with psychic people and lycomorphs (aka werewolves if werewolves were humans rapidly devolving/re-evolving into a stem mammal-like beast form), Roach is from a dumpy vampire world, Mauve is from an edgy Pokemon AU me and my gf made, and Ancha (sometimes also called Alice in AUs) exists in a surreal seapunk Atlantis and Dylan tags along.
I like, have thought way too much about these guys and welcome questions about them.
Well, nope! Tetraceratops was actually a small synapsid (a “proto-mammal”) from the Early Permian of Texas, USA, living about 279-272 million years ago. Known only from a 9cm long skull (3.5″), it had two sets of saber teeth in its jaws and a total of six horns on its face instead of four – two on its snout, two in front of its eyes, and two at the back of its jaws.
It’s unclear exactly what the rest of its body looked like, or even where it belongs in the synapsid family tree – but currently it’s thought to be the earliest known member of the therapsids. I’ve reconstructed it here to look similar to other basal therapsids like Herpetoskylax.
Only about 50cm long (~19.5in), these tubby little creatures were one of the few survivors of the worst mass extinction in Earth’s history. For a few million years after the extinction the various species of Lystrosaurus were so successful that they were the single most common land vertebrate in the world, making up 95% of the population.
Guess who? They are the only flying mammals, they kill mosquitoes and they sleep upside down - BATS! October is Bat Appreciation Month, thanks to BLM Idaho for sharing these great bat photos on public lands.
Researchers observe stem cell specialization in the brain
Adult stem cells are flexible and can transform themselves into a wide variety of special cell types. Because they are harvested from adult organisms, there are no ethical objections to their use, and they
therefore open up major possibilities in biomedicine. For instance,
adult stem cells enable the stabilization or even regeneration of
damaged tissue. Neural stem cells form a reservoir for nerve cells.
Researchers hope to use them to treat neurodegenerative disorders such
as Parkinson’s and Alzheimer’s disease. Tübingen researchers led by
Professor Olga Garaschuk of the University of Tübingen’s Institute for
Physiology, working with colleagues from Yale University, the Max Planck
Institute of Neurobiology in Martinsried and the Helmholtz Center in
Munich, studied the integration of these cells into the pre-existing
neural network in the living organism. The results of their study have
been published in the latest edition of Nature Communications.
There are only two places in the brains of adult mammals where stem
cells can be found – the lateral ventricles and the hippocampus. These
stem cells are generating neurons throughout life. The researchers
focused on a stem cell zone in the lateral ventricle, from where
progenitors of the nerve cells migrate towards the olfactory bulb. The
olfactory nerves which start in the nasal tissue run down to this
structure, which in mice is located at the frontal base of the brain. It
is there that the former stem cells specialized in the task of
processing information on smells detected by the nose. “Using the latest
methods in microscopy, we were for the first time able to directly
monitor functional properties of migrating neural progenitor cells
inside the olfactory bulb in mice,” says Olga Garaschuk. The researchers
were able to track the cells using special fluorescent markers whose
intensity changes according to the cell’s activity.
The study showed that as little as 48 hours after the cells had
arrived in the olfactory bulb, around half of them were capable of
responding to olfactory stimuli. Even though the neural progenitor cells
were still migrating, their sensitivity to odorants and their
electrical activity were similar to those of the surrounding, mature
neurons. The mature pattern of odor-evoked responses of these cells
strongly contrasted with their molecular phenotype which was typical of
immature, migrating neuroblasts. “Our data reveal a remarkably rapid
functional integration of adult-born cells into the pre-existing neural
network,” says Garaschuk, “and they show that sensory-driven activity is
in a position to orchestrate their migration and differentiation as
well as their decision of when and where to integrate.”