Did T. rex Have Feathers and What Color Were They? Adult Tyrannosaurus rex were likely mostly scaly, with no confirmed body-covering feathers, though small patches of simple filaments in juveniles or limited areas cannot be ruled out. No direct evidence exists for T. rex coloration, and bright purple or green plumage is unlikely because such hues usually require feather structures or pigments not yet documented for tyrannosaurids. Evidence from related species and preserved skin impressions points to muted, functional tones rather than tropical-bird displays for large tyrannosaurids.

Scales, feathers, or both? Evidence points to mostly scaly adult T. rex, with possible fuzzy juveniles—and color hints preserved in melanosomes. What do you picture? #DinosaurColor #Dinosaurs #Feathers #Melanosomes #TRex

HLA export by melanoma cells decoys cytotoxic T cells to promote immune evasion Melanoma cells escape immune surveillance by releasing MHC-antigen-loaded large EVs, known as melanosomes, that directly engage and impair CD8+ T cell receptors.

#WeekendRead! #SmartTumor #EveryCellIsAnImmuneCell! Levy & (many) friends show @cp-cell.bsky.social that melanoma tumors release large extracellular vesicles #melanosomes decorated with MHC-I & high affinity tumor associated antigens which subvert cytotoxic T cells! www.cell.com/cell/fulltex...

📰New & Featured | A study in #Cell discovered that secretion of #melanosomes can be blocked to enhance tumor #immunity
🔹Presence of melanosomes➡️poor prognosis + reduced T cell cytotoxicity + less responsive to immunotherapy
🔹Melanosome carry #TAAs and #neoantigens
#Melanoma

Image credit: Valentina Rossi

But on a microstructural level, the story is different. Using #SEM imaging, we identified #melanosomes (melanin-bearing cells) and analysed their shape @ucc.ie. They turned out to be most similar to feathers among skin tissue types in amniotes.

Paleontologists Stumble Across 15-Million-Year-Old Fish Fossils That Are So Well Preserved, Their Last Meals Are Intact Discovered in Australia, the fossils represent a new species that lived during the Miocene epoch and highlight how iron-rich rock can protect specimens over time

🎨 Scientists just reconstructed the color of a 15-million-year-old fish for the first time using fossilized pigment cells!

Ferruaspis brocksi had a striped body, pale belly & dark back—thanks to well-preserved #melanosomes in iron-rich #goethite rock. #Miocene
www.smithsonianmag.com/smart-news/p...

Dinosaur-era mammals’ fur color revealed for first time Preserved pigments suggest Jurassic mammals had dark fur, consistent with a nocturnal lifestyle

#adaptation
#melanosomes
#biochemistry

Sunday just so story

How mammals of the Mesozoic with uniform dark brown and nocturnal habits to better avoid being noticed by giant dinosaurs, acquired many coloured striped and spotted furs after the giants became extinct.