Andrej Spiridonov
@andrejpaleo.bsky.social
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
https://twitter.com/AndrejSpiridon4
More on the rise and fall of taxa and the biases in the estimation of their dynamics:
"...the occupancy trajectories of marine animal genera look to be a relatively gradual rise post-origination with a sudden decline before extinction."
doi.org/10.1017/pab....
🧪 ⚒️ #Paleobio #EvoBio #Macroecology
"...the occupancy trajectories of marine animal genera look to be a relatively gradual rise post-origination with a sudden decline before extinction."
doi.org/10.1017/pab....
🧪 ⚒️ #Paleobio #EvoBio #Macroecology
February 9, 2026 at 11:45 PM
More on the rise and fall of taxa and the biases in the estimation of their dynamics:
"...the occupancy trajectories of marine animal genera look to be a relatively gradual rise post-origination with a sudden decline before extinction."
doi.org/10.1017/pab....
🧪 ⚒️ #Paleobio #EvoBio #Macroecology
"...the occupancy trajectories of marine animal genera look to be a relatively gradual rise post-origination with a sudden decline before extinction."
doi.org/10.1017/pab....
🧪 ⚒️ #Paleobio #EvoBio #Macroecology
When you talk about the process of macroevolution (and beyond the reconstruction of phylogenetic trees based on some useful conventions) the budding speciation and the question of direct ancestry becomes a mechanistic expectation.
February 9, 2026 at 7:28 AM
When you talk about the process of macroevolution (and beyond the reconstruction of phylogenetic trees based on some useful conventions) the budding speciation and the question of direct ancestry becomes a mechanistic expectation.
A Bretskyan hierarchy perspective on the role of geology and rivers in the diversification of freshwater fishes by James Albert and co.
onlinelibrary.wiley.com/doi/full/10....
🧪 ⚒️ #Paleobio #Geology #EvoBio #Macroecology
onlinelibrary.wiley.com/doi/full/10....
🧪 ⚒️ #Paleobio #Geology #EvoBio #Macroecology
![A synthesis of relationships between geological time [logscale; million years ago (Ma)] and mitochondrial DNA sequencedivergence among freshwater lineages](https://cdn.bsky.app/img/feed_thumbnail/plain/did:plc:qb6x3o2dt7vkteqeqrqpjtxc/bafkreifnephjz42sazyxa3ceafzmscxduwij6524cqa54ezvgod6oo7hbi@jpeg)
February 8, 2026 at 11:09 PM
A Bretskyan hierarchy perspective on the role of geology and rivers in the diversification of freshwater fishes by James Albert and co.
onlinelibrary.wiley.com/doi/full/10....
🧪 ⚒️ #Paleobio #Geology #EvoBio #Macroecology
onlinelibrary.wiley.com/doi/full/10....
🧪 ⚒️ #Paleobio #Geology #EvoBio #Macroecology
February 7, 2026 at 4:34 PM
Interesting case of recent human-modulated geodispersal which was enabled by the building and functioning of the Suez Canal. Interesting to think about this case as an analogue of ancient tectonic restructuring of seaways 👇
t.co/k6Qdu82nti
🧪 ⚒️ #Paleobio #Geology #Macroecology #Biogeography
t.co/k6Qdu82nti
🧪 ⚒️ #Paleobio #Geology #Macroecology #Biogeography
February 6, 2026 at 7:33 AM
Interesting case of recent human-modulated geodispersal which was enabled by the building and functioning of the Suez Canal. Interesting to think about this case as an analogue of ancient tectonic restructuring of seaways 👇
t.co/k6Qdu82nti
🧪 ⚒️ #Paleobio #Geology #Macroecology #Biogeography
t.co/k6Qdu82nti
🧪 ⚒️ #Paleobio #Geology #Macroecology #Biogeography
Reposted by Andrej Spiridonov
Scientists just found that a curious group of plankton began to flourish rapidly after the dino-killing asteroid—a key sign life was on the mend.
They made their discovery by measuring the slow accumulation of space dust after the impact.
#Paleontology #PlankticForams
New for @science.org 🧪🏺
They made their discovery by measuring the slow accumulation of space dust after the impact.
#Paleontology #PlankticForams
New for @science.org 🧪🏺
Space dust reveals rapid evolution after dino-killing asteroid
New data detail how tiny forms of life rebounded much more quickly than previously believed
www.science.org
February 5, 2026 at 1:10 AM
Scientists just found that a curious group of plankton began to flourish rapidly after the dino-killing asteroid—a key sign life was on the mend.
They made their discovery by measuring the slow accumulation of space dust after the impact.
#Paleontology #PlankticForams
New for @science.org 🧪🏺
They made their discovery by measuring the slow accumulation of space dust after the impact.
#Paleontology #PlankticForams
New for @science.org 🧪🏺
Thanks for tagging, Sergi. Cool and relevant study!
February 5, 2026 at 12:39 PM
Thanks for tagging, Sergi. Cool and relevant study!
Reposted by Andrej Spiridonov
The billionaire class wants to decimate the white collar workforce. Because white collar workers are expensive. And because white collar workers—who historically sided with billionaires—are questioning that alliance. Which makes their knowledge and resources a huge threat to billionaire power.
February 5, 2026 at 11:03 AM
The billionaire class wants to decimate the white collar workforce. Because white collar workers are expensive. And because white collar workers—who historically sided with billionaires—are questioning that alliance. Which makes their knowledge and resources a huge threat to billionaire power.
Reposted by Andrej Spiridonov
We have used #recurrence_plot based methods to study the "High predictability potential of highly synchronized widespread floods in monsoon regions" – useful approach for forecasting future widespread flood events.
doi.org/10.1016/j.jh...
doi.org/10.1016/j.jh...
Redirecting
doi.org
February 4, 2026 at 12:35 PM
We have used #recurrence_plot based methods to study the "High predictability potential of highly synchronized widespread floods in monsoon regions" – useful approach for forecasting future widespread flood events.
doi.org/10.1016/j.jh...
doi.org/10.1016/j.jh...
The Paleontological Research Institution invites applications from undergraduate students, graduate students, and post-doctoral researchers for the 2026 John W. Wells Grants-in-Aid of Research Program who want to visit PRI collections
www.priweb.org/collections/...
Deadline is March 2, 2026.
www.priweb.org/collections/...
Deadline is March 2, 2026.
Grant Opportunities — Paleontological Research Institution
www.priweb.org
February 5, 2026 at 9:49 AM
Interesting perspective on the interaction of pyrodiversity and the biodiversity. One more case showing the importance of the creative destruction and abiotic (here more of a blurred interactive 'bio-abiotic') factors in keeping biotic structure.
www.nature.com/articles/s43...
🧪 ⚒️ #Macroecology
www.nature.com/articles/s43...
🧪 ⚒️ #Macroecology
February 5, 2026 at 7:47 AM
Interesting perspective on the interaction of pyrodiversity and the biodiversity. One more case showing the importance of the creative destruction and abiotic (here more of a blurred interactive 'bio-abiotic') factors in keeping biotic structure.
www.nature.com/articles/s43...
🧪 ⚒️ #Macroecology
www.nature.com/articles/s43...
🧪 ⚒️ #Macroecology
February 5, 2026 at 6:01 AM
Popular article on our recent discovery of the scaling laws of empirical geochronologies:
scienmag.com/exploring-te...
🧪 ⚒️ #Geology #Paleobio #Climate
scienmag.com/exploring-te...
🧪 ⚒️ #Geology #Paleobio #Climate
Exploring Temporal Fluctuations in Multifractal Geochronologies
In a groundbreaking study set for publication in the journal Commun Earth Environ in 2026, researchers led by Lovejoy, S., along with Davies, R., and Spiridonov, A., delve into the intricacies of time
scienmag.com
February 3, 2026 at 1:23 PM
Popular article on our recent discovery of the scaling laws of empirical geochronologies:
scienmag.com/exploring-te...
🧪 ⚒️ #Geology #Paleobio #Climate
scienmag.com/exploring-te...
🧪 ⚒️ #Geology #Paleobio #Climate
Survival bias of the ocean floor certainly affects our perception on the igneous sources of global perturbations, including mass extinction events. There are no strict rules on why only terrestrial LIPs could trigger catastrophes.
The study itself:
doi.org/10.1130/G534...
🧪 #Geology ⚒️ #Paleobio
The study itself:
doi.org/10.1130/G534...
🧪 #Geology ⚒️ #Paleobio
Marine large igneous provinces: Key drivers of Triassic recurrent extinction | Geology | GeoScienceWorld
The trigger for frequent extinctions during the Phanerozoic remains a persistent and unresolved frontier issue in Earth sciences. We present a detailed
doi.org
February 2, 2026 at 10:43 PM
Survival bias of the ocean floor certainly affects our perception on the igneous sources of global perturbations, including mass extinction events. There are no strict rules on why only terrestrial LIPs could trigger catastrophes.
The study itself:
doi.org/10.1130/G534...
🧪 #Geology ⚒️ #Paleobio
The study itself:
doi.org/10.1130/G534...
🧪 #Geology ⚒️ #Paleobio
Parasite-induced rostra of Jurassic belemnites:
"The absence of any external injury corroborated by high-resolution computed tomography suggests parasitism as the most probably cause for shell deformation."
app.pan.pl/archive/publ...
🧪 #Geology ⚒️ #Paleobio
"The absence of any external injury corroborated by high-resolution computed tomography suggests parasitism as the most probably cause for shell deformation."
app.pan.pl/archive/publ...
🧪 #Geology ⚒️ #Paleobio
February 1, 2026 at 12:31 AM
Parasite-induced rostra of Jurassic belemnites:
"The absence of any external injury corroborated by high-resolution computed tomography suggests parasitism as the most probably cause for shell deformation."
app.pan.pl/archive/publ...
🧪 #Geology ⚒️ #Paleobio
"The absence of any external injury corroborated by high-resolution computed tomography suggests parasitism as the most probably cause for shell deformation."
app.pan.pl/archive/publ...
🧪 #Geology ⚒️ #Paleobio
This digital machine learning reconstruction could be a real breakthrough in the specimen paleontology. A good use of AI.
"The oldest sepioid cephalopod from the Cretaceous discovered by Digital fossil-mining with zero-shot learning AI"
www.nature.com/articles/s42...
🧪 #Geology ⚒️ #Paleobio #EvoBio
"The oldest sepioid cephalopod from the Cretaceous discovered by Digital fossil-mining with zero-shot learning AI"
www.nature.com/articles/s42...
🧪 #Geology ⚒️ #Paleobio #EvoBio
January 30, 2026 at 10:44 PM
This digital machine learning reconstruction could be a real breakthrough in the specimen paleontology. A good use of AI.
"The oldest sepioid cephalopod from the Cretaceous discovered by Digital fossil-mining with zero-shot learning AI"
www.nature.com/articles/s42...
🧪 #Geology ⚒️ #Paleobio #EvoBio
"The oldest sepioid cephalopod from the Cretaceous discovered by Digital fossil-mining with zero-shot learning AI"
www.nature.com/articles/s42...
🧪 #Geology ⚒️ #Paleobio #EvoBio
Yes, the durations of gaps are affected by noise as well as the structure of sampling. Either way, this is the data you actually have at hand before the more advanced derivative analyses. The point here is that the structure of gaps have very specific form: it shows scaling with multiple regimes.
January 30, 2026 at 3:12 PM
Yes, the durations of gaps are affected by noise as well as the structure of sampling. Either way, this is the data you actually have at hand before the more advanced derivative analyses. The point here is that the structure of gaps have very specific form: it shows scaling with multiple regimes.
At time scales of hundreds of millions to billions of Ma correlation between temperatures and measurement densities becomes increasingly close, thus highlighting the possibility that we should pay special attention in trying to reconstruct trends at the longest time scales.
5/5
5/5
January 29, 2026 at 10:09 PM
At time scales of hundreds of millions to billions of Ma correlation between temperatures and measurement densities becomes increasingly close, thus highlighting the possibility that we should pay special attention in trying to reconstruct trends at the longest time scales.
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This suggests that there is a common cause and a very specific bias in the distribution of gaps or conversely paleoclimatological measurements, directly related to the tempos of geodynamic, sedimentological functioning, and stratigraphical reflections of the planet Earth.
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4/5
January 29, 2026 at 10:06 PM
This suggests that there is a common cause and a very specific bias in the distribution of gaps or conversely paleoclimatological measurements, directly related to the tempos of geodynamic, sedimentological functioning, and stratigraphical reflections of the planet Earth.
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What is more interesting these gaps in sections reveal similar scaling regimes to that of surface temperatures, with scaling breaks and crossovers between macroweather-climate, climate-macroclimate, macroclimate-megaclimate time scales.
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January 29, 2026 at 10:06 PM
What is more interesting these gaps in sections reveal similar scaling regimes to that of surface temperatures, with scaling breaks and crossovers between macroweather-climate, climate-macroclimate, macroclimate-megaclimate time scales.
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3/5
The gaps are neither uniform nor Gaussian. As it turns out, they are scaling, and multifractal, meaning that the moments of their distributions diverge as we zoom-inn.
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January 29, 2026 at 10:03 PM
The gaps are neither uniform nor Gaussian. As it turns out, they are scaling, and multifractal, meaning that the moments of their distributions diverge as we zoom-inn.
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2/5
I'm glad to share our new study on the nature of distributions of gaps in empirical geochronologies of geological section as a function of time scale. Measurements of proxies are highly uneven if measured through time.
1/5
www.nature.com/articles/s43...
🧪 #Geology ⚒️ #Paleobio #EvoBio
1/5
www.nature.com/articles/s43...
🧪 #Geology ⚒️ #Paleobio #EvoBio
January 29, 2026 at 10:02 PM
I'm glad to share our new study on the nature of distributions of gaps in empirical geochronologies of geological section as a function of time scale. Measurements of proxies are highly uneven if measured through time.
1/5
www.nature.com/articles/s43...
🧪 #Geology ⚒️ #Paleobio #EvoBio
1/5
www.nature.com/articles/s43...
🧪 #Geology ⚒️ #Paleobio #EvoBio
