@andrejpaleo
Professor of paleontology and Earth systems at Vilnius University. My interests are: theoretical paleontology, evolution, geology, stratigraphy, philosophy of biology and geology, climate at scales great and small. https://twitter.com/AndrejSpiridon4
Reproduction of multicellular organisms emerges as an exaptation of their ecology
"...our results show that developmental regulation evolves through co-option of ecological interactions during the transition to multicellularity."
CC: @svalver.bsky.social
🧪 #Paleobio #EvoBio
Weird and wonderful world of the early Mesozoic
🧪 ⚒️ #Geology #Paleobio
"Stem tetrapod" from the Early Permian. You can think about it as a "living fossil" holdover from the earliest Carboniferous. But as Jason and others explain it was specialized in its dentition, completely weird and possibly was herbivorous!
🧪 ⚒️ #Geology #Paleobio #EvoBio
This is what ecocide looks like.
A popular article about our recent study on the nature of measurement gaps and their scaling in empirical chronologies.
www.riverreporter.com/stories/time...
🧪 ⚒️ #Geology #Paleobio #EvoBio
They blew up an elementary school Tom
www.theatlantic.com/ideas/2026/0...
The squids was the "soft-bodied thing" Pluridens imelaki ate. Starting from the Cenomanian, squids started their numerical dominance over other forms of cephalopods. They became the sea-food for large pelagic animals.
doi.org/10.1126/scie...
🧪 ⚒️ #Geology #Paleobio #EvoBio
What a splendid graptolite specimen!
Wow, osteichthyan from the early Silurian (Telychian, 436 Ma):
"Phylogenetic analysis places Megamastax within the osteichthyan stem, near the
osteichthyan crown-group node"
🧪 ⚒️ #Geology #Paleobio #EvoBio
Summary of inverse thermal histories of cratonic interiors in the context of Earth systems evolution
The extreme unevenness in the completeness of the stratigraphic, and by implication fossil, record is formed by many processes. Apparently the most profound gap— the Great Unconformity, is driven by tectonics.
www.pnas.org/doi/10.1073/...
🧪 ⚒️ #Geology #Paleobio
For Europe is better to stay the fuck out of this deadly gamble
Salt as the record of geological history and the multifaceted resource.
CC: @kagiadi.bsky.social
🧪 ⚒️ #Geology
Dynamic balance of plants and megafauna on the geological time scales and not a succession👇
"Revisiting Europe's temperate forests: Palaeoecological evidence for an herbivory-driven woodland-grassland mosaic biome"
www.sciencedirect.com/science/arti...
🧪 ⚒️ #Geology #Paleobio #Macroecology
Stunning landscapes from the Early Pleistocene dawn of humanity in Africa
🧪 ⚒️ #Geology #Paleobio #EvoBio
Frequencies of unique and repeated innovations through time. Light gray = unique; dark gray = repeated; black = total. (A) Raw data. (B) Normalized for period duration.
Local and time evolving ergodicity of mollusk evolution:
"We interpret this finding to mean that molluscan evolutionary history has become substantially more predictable over time despite increasing diversity"
www.pnas.org/doi/epdf/10....
🧪 ⚒️ #Geology #Paleobio #EvoBio
Yes, rates show synchrony, and the diversity trajectories of separate clades emerge from the small asymmetries.
Speciation, extinction, net rate, and biodiversity curves for fixed benthos. (A-C) Brachiopoda. (D-F) Echinodermata. (G-I) Bryozoa. (J-L) Porifera. (M-O) Cnidaria.
"the Cambrian Explosion, the Great Ordovician Biodiversification Event (GOBE), and the Late Ordovician Mass Extinction (LOME)... traditional understanding of these events ...masks the complex dynamics of individual clades"
www.sciencedirect.com/science/arti...
🧪 ⚒️ #Geology #Paleobio #EvoBio
Title of the discussed study: "Discrete turn strategies emerge in information-limited navigation"
Numerical optimal strategies for run & tumble, steering, and reversing.
Helminthopsis
Helminthoidichnites
These kinds of studies are extremely important in deciphering from the mechanistic point-of-view the evolution of behaviors using time-calibrated trace fossil record.
First photo - Helminthopsis.
Second photo - Helminthoidichnites.
arxiv.org/abs/2602.23324
🧪 ⚒️ #Geology #Paleobio #EvoBio
Cool! Right illustration to the Yesterday's discussion.
Liudas Daumantas presents his dissertation.
Liudas Daumantas after the defense.
Gift to the supervisor.
Today (now my former PhD student) Liudas Daumantas defended his dissertation on the machine learning approaches in revealing the Bretskyan hierarchy of geobiomes.
Approximately 20 million vertebrate animals, moslty mice, are used in research each year. Some comparisons on agricultural use.
Maybe. But, given the current trend towards aggressive policies dedicated to the full compliance of smaller states in the "spheres of influence", who knows where is the real truth?
What if? 🤔
This estimate for max size sounds much more reasonable.
1 ton polar bear is far away from the typical average size for the species. If average over males and females this should be 1/3 of that or something.
Models and actual dinosaur tracks/trace fossils
XY plots presenting the landmark locations for each sediment consistency in each examined layer.
Significant implications on the ichnology->taphonomy-->biology mapping
"Tracks exposed along subsurface layers had morphologies more robust to changes in sediment properties than the surface tracks."
royalsocietypublishing.org/rsif/article...
🧪 ⚒️ #Geology #Paleobio #EvoBio
Best practices for moving from correlation to causation in ecological research
🧪 #Macroecology
More features you have, and more complex they are, the more vulnerabilites they will have on average. That's how the 'black boxes' work.
Prototaxites goes brrrrr
🧪 ⚒️ #Geology #Paleobio #EvoBio
This is what evolution can do with a deer-like even toed who uncarefully stepped and stayed into the water...