Rosa Rubicondior: Refuting Creationism - Another Plethora of Transitional Fossils - From 250 Million Years Before 'Creation Week'

iv> Fresh fossil finds in Africa shed light on the era before Earth’s largest mass extinction | UW News

An artistic rendering of an evening approximately 252 million years ago during the late Permian in the Luangwa Basin of Zambia. The scene includes several saber-toothed gorgonopsians and beaked dicynodonts.

Gabriel Ugueto

Another day, and another clutch of transitional fossils from millions of years before “Creation Week” for creationists to lie about, misrepresent, or simply ignore in order to cope with the resulting cognitive dissonance. This time, it’s not just a single research paper, but a series of 14 published in the Journal of Vertebrate Paleontology.

The fossils are the result of 15 years of excavation at three sites in Africa and cover the 47-million-year Permian era, which ended with the “Great Dying” 252 million years ago — the mass extinction at the end of the Permian in which an estimated 70% of species became extinct. Not only is that timeline fatal to those creationists who like to imagine the Earth and life on it are just 6,000 to 10,000 years old, but the fact of a mass extinction raises insurmountable problems for intelligent design advocates. They would need to explain the intelligence behind designing species only to have them wiped out by a climate catastrophe — one which should have been anticipated by an omniscient designer and could have been prevented by an omnipotent god.

And of course, another problem for creationists is the abundance of these transitional fossils, which, according to creationist dogma, should not exist at all.

African Fossil Sites.

Top left: Map of the Ruhuhu Basin in southern Tanzania, with local formations and fossil localities highlighted [1, 2].
Top right: Generalized geology and stratigraphic relationships within the Songea Group (which includes the Ruhuhu and Usili formations) [3].
Bottom left: Detailed stratigraphic map pinpointing local sectors of the Ruhuhu Basin, including the Usili and Ruhuhu formations [4].
Bottom right: Permian paleogeographic reconstruction (~270 Ma), situating the southern African Karoo basins (including Ruhuhu and Luangwa) in the context of Pangaea [5].

Ruhuhu Basin (Southern Tanzania)

Geological Overview
The Ruhuhu Basin is a Paleozoic rift basin within the Songea Group, comprising up to 3,000 m of stratified deposits from the Upper Carboniferous to Middle Triassic [2].

Key formations include:

Ruhuhu Formation (~500 m thick): A lacustrine mudrock sequence with stromatolitic carbonates and oolitic layers in lower and middle parts, and fluvial-conglomeratic sandstones in upper sections [2, 6]. Its age spans the middle to late Permian, covering the mid–late Permian boundary [2].
Usili Formation (~260 m thick): A Late Permian (Lopingian) fluvio-lacustrine succession—starting with conglomeratic/alluvial layers that grade upward into coarse cross-bedded sandstones, then nodular siltstones and laminated mudstones interspersed with ribbon sandstones [7]. The Usili Formation correlates with South Africa’s Cistecephalus and Dicynodon Assemblage Zones, as well as the Zambian Upper Madumabisa Mudstone, situating it firmly in the late Permian [7].

Dating and Significance

Fossils from the Usili Formation provide critical evidence of diverse Permian therapsids, pareiasaurs, archosauromorphs, and amphibians, directly preceding the end-Permian mass extinction [7].

Luangwa Basin (Eastern Zambia)

Geological Context

The Luangwa Basin also contains extensive Permo‑Triassic Karoo sequences, potentially reaching up to 8,000 m thick [8]. The fossiliferous Permian layers are chiefly within the Madumabisa Mudstone Formation.

Stratigraphy and Dating

The upper Madumabisa Mudstone Formation has been biostratigraphically linked with the Cistecephalus Assemblage Zone of South Africa, corresponding to the Wuchiapingian stage of the Late Permian (early Lopingian) [9].

Notable finds:

Kembawacela, a cistecephalid dicynodont, hails from the upper Madumabisa Mudstone and aligns stratigraphically with the Wuchiapingian to early Changhsingian (Late Permian) [10]
Other fossils, including pareiasaur remains and tapinocephalid teeth, have been recovered from the broader Mid‑Zambezi Basin stratigraphy, indicating the complexity and richness of vertebrate fossil records in this region [11].

Mid-Zambezi Basin (Southern Zambia)

Geological Structure

The Mid‑Zambezi Basin is a half‑graben formed by extensional tectonics. It features a sharp boundary fault on its northwestern margin, while the southeastern side consists of alternating half‑graben systems [12].

Dating and Paleoenvironment

Palynological analyses (though still limited) from regions such as Siamwiinga and Sianyolo are working to refine stratigraphic resolution and interpret depositional environments and hydrocarbon source potential [12]. Biozones within the Madumabisa Mudstone show affinities to assemblages seen in Australia and may predate the end-Guadalupian extinction, suggesting they capture important ecological transitions near the end-Permian era [13].

Geological Formation Summary:

Ruhuhu Basin:

Key formation - Ruhuhu (middle–late Permian), Usili (Late Permian)

Geological Age / Biozone - Middle–Late Permian; correlates with South African Cistecephalus & Dicynodon zones

Significance - Rich therapsid diversity pre-extinction

Luangwa Basin:

Key formation - Upper Madumabisa Mudstone

Geological Age - Wuchiapingian–early Changhsingian (Late Permian)

Significance - Contains endemic dicynodonts such as Kembawacela

Mid-Zambezi Basin:

Key formation: - Madumabisa Mudstone; palynological horizons

Geological age: - Pre-Guadalupian to Late Permian

Significance: - Promising for refined biostratigraphy & paleoenvironment

In Summary

Ruhuhu Basin offers a finely resolved view of terrestrial ecosystems from the mid to late Permian, especially through the Ruhuhu and Usili formations.
Luangwa Basin, through the Madumabisa Mudstone, holds evidence of significant Late Permian fauna with good biostratigraphic correlations to Karoo biozones.
Mid-Zambezi Basin remains promising for further study, particularly with palynological insights that may anchor broader regional and even global Permian stratigraphy.

An account of the work behind these 14 papers is given in a news release from the University of Washington by James Urton.

Fresh fossil finds in Africa shed light on the era before Earth’s largest mass extinction
An international team of paleontologists has spent more than 15 years excavating and studying fossils from Africa to expand our understanding of the Permian, a period of Earth’s history that began 299 million years ago and ended 252 million years ago with our planet’s largest and most devastating mass extinction. Led by researchers at the University of Washington and the Field Museum of Natural History, the team is identifying the animals that thrived in southern Pangea — the planet’s single supercontinent at the time — just before the so-called “Great Dying” wiped out about 70% of terrestrial species, and an even larger fraction of marine ones.

This mass extinction was nothing short of a cataclysm for life on Earth, and changed the course of evolution. But we lack a comprehensive view of which species survived, which didn’t, and why. The fossils we have collected in Tanzania and Zambia will give us a more global perspective on this unprecedented period in our planet’s natural history.

Professor Christian Sidor, co-editor of the 14 papers
Curator of vertebrate paleontology
Department of Biology and Burke Museum of Natural History
University of Washington, Seattle, Washington, USA.

Sidor and Kenneth Angielczyk, curator of paleomammalogy at the Field Museum, are co-editors of a 14-article series published Aug. 7 in the Journal of Vertebrate Paleontology featuring the team’s recent discoveries about the myriad of animals that made Permian Africa their home. These include saber-toothed predators, burrowing foragers and a large, salamander-like creature.

All these finds were excavated in three basins across southern Africa: the Ruhuhu Basin in southern Tanzania, the Luangwa Basin in eastern Zambia and the Mid-Zambezi Basin in southern Zambia. Most were discovered by team members on multiple, month-long excavation trips to the region over the past 17 years. Others were analyses of specimens dug up decades prior that had been stored in museum collections.

These parts of Zambia and Tanzania contain absolutely beautiful fossils from the Permian. They are giving us an unprecedented view of life on land leading up to the mass extinction.

Professor Christian Sidor.

Jacqueline Lungmus, an assistant professor of geosciences at the University of Oklahoma and UW undergraduate alum; Kenneth Angielczyk, curator of paleomammology at the Field Museum; and Brandon Peecook, associate professor of biological sciences at Idaho State University and a UW doctoral alum, excavate a fossilized dicynodont from the Permian of Zambia.

Roger Smith/University of the Witwatersrand.

Starting in 2007, Sidor and his team, including UW students and postdoctoral researchers, made five trips to the Ruhuhu Basin and four to the Mid-Zambezi and Luangwa basins, all in cooperation with the Tanzanian and Zambian governments. The researchers trekked between field sites miles apart to collect fossils. They stayed in villages or camped in the open — once waking during the night to the ground-quaking stomps of a nearby elephant herd. All fossils collected by the team will be returned to Tanzania and Zambia after researchers have completed their analyses.

The Permian is the endpoint of what paleontologists call the Paleozoic Era. During this time, animal life — which evolved first in Earth’s oceans — began to colonize land and complex terrestrial ecosystems developed. By the Permian, a diverse array of amphibian and reptile-like creatures roamed environments ranging from early forests to arid valleys. The end-Permian mass extinction — whose precise cause scientists are still debating — obliterated many of these ecosystems and ushered in the Mesozoic Era, which saw the evolution of dinosaurs, as well as the first birds, flowering plants and mammals.

For decades, scientists’ best understanding of the Permian, the Great Dying and the start of the Mesozoic came from the Karoo Basin in South Africa, which contains a near-complete fossil record of periods before and after the mass extinction. But beginning in the 1930s, paleontologists realized that basins in Tanzania and Zambia contain fossil records of this time range that are almost as pristine as the Karoo’s. The excavation trips by Sidor, Angielczyk and their colleagues represent the largest analysis to date of the region’s fossil record from before and after the Great Dying. In 2018, they published a comprehensive analysis of the post-Permian animals of the Ruhuhu and Luangwa basins. These new papers look further back into the Permian.

A map of Zambia and Tanzania in southern Africa showing the locations of the three basins visited by the team, the Luangwa and Mid-Zambezi basins in Zambia and the Ruhuhu Basin in Tanzania.

Christian Sidor/University of Washington

The number of specimens we’ve found in Zambia and Tanzania is so high and their condition is so exquisite that we can make species-level comparisons to what paleontologists have found in South Africa. I know of no better place on Earth for getting sufficient detail of this time period to make such detailed conclusions and comparisons.

Professor Christian Sidor.

The team’s papers describe a number of new species of dicynodonts. These small, burrowing, reptile-like herbivores first evolved in the mid-Permian. By the time of the mass extinction, dicynodonts — many of whom sported a beak-like snout with two small tusks that likely aided burrowing — were the dominant plant-eaters on land. The team’s findings also include several new species of large, saber-toothed predators called gorgonopsians, as well as a new species of temnospondyl, a large salamander-like amphibian.

We can now compare two different geographic regions of Pangea and see what was going on both before and after the end-Permian mass extinction. We can really start to ask questions about who survived and who didn’t.

Professor Christian Sidor.

In addition to the UW and the Field Museum, the team includes scientists from the University of Chicago, Loyola University Chicago, Idaho State University, the National Museum of Natural History in Paris, Carleton University, the University of Southern California, the University of the Witwatersrand in South Africa, the Iziko South African Museum, Southern Methodist University, the North Carolina Museum of Natural Sciences, the Museum for Natural History in Berlin, the U.S. Geological Survey, the University of Oklahoma, the National Heritage Conservation Commission in Lusaka, Virginia Tech, and the Chipembele Wildlife Education Center in Mfume, Zambia. Seven of these scientists are former UW postdoctoral researchers, doctoral students or undergraduate students. The research was funded by the U.S. National Science Foundation and the National Geographic Society.

Publications:

Christian A. Sidor & Kenneth D. Angielczyk
Introduction to vertebrate evolution in the Permian rift basins of Tanzania and Zambia
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2446616
Roger M. H. Smith, Christian A. Sidor, Kenneth D. Angielczyk, Sterling J. Nesbitt, J-Sébastien Steyer & Neil J. Tabor
Origin of conglomerate-hosted bonebeds at the base of the upper Permian Usili Formation, Ruhuhu Basin, Tanzania
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2025.2466442
J.-Sébastien Steyer & Christian A. Sidor
The first Paleozoic temnospondyl from Zambia: a new species of Rhineceps from the Permian Madumabisa Mudstone Formation, Mid-Zambezi Basin
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2025.2451312
Xavier A. Jenkins, Claire Browning, Jonah Choiniere & Brandon R. Peecook
A new moradisaurine captorhinid from the Upper Permian (Lopingian) upper Madumabisa Mudstone Formation (Luangwa Basin) of Zambia Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2427529
Christian F. Kammerer, Kenneth D. Angielczyk & Jörg Fröbisch
Permian origins of the Lystrosauridae (Therapsida: Dicynodontia)
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2025.2451813
Henry N. Thomas, Kenneth D. Angielczyk & Brandon R. Peecook
The first geikiid dicynodont, Aulacephalodon kapoliwacela, sp. nov. (Therapsida, Anomodontia), from the upper Madumabisa Mudstone Formation, Zambia
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2446603
Kenneth D. Angielczyk & Benjamin K. A. Otoo
A new cryptodont dicynodont (Therapsida, Anomodontia) from the Lopingian Usili Formation, Ruhuhu Basin, Tanzania
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2441898
Brenlee K. Shipps, Christian A. Sidor & Kenneth D. Angielczyk
Dicynodontoides kubwa, sp. nov. (Synapsida: Anomodontia), a new large emydopoid from the base of the Usili Formation (Ruhuhu Basin, Tanzania)
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2440112
Caroline P. Abbott, Selena A. Martinez, Jacqueline K. Lungmus, Isaac Magallanes & Kenneth D. Angielczyk
The postcranial anatomy of Kembawacela kitchingi (Therapsida, Anomodontia) and the functional diversity of cistecephalid forelimbs Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2025.2486068
Zoe T. Kulik
Bone histology of a gorgonopsian skeleton from the upper Madumabisa Mudstone Formation, Zambia Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2025.2490799
Alex Acker, Brandon R. Peecook, Christian A. Sidor & Megan R. Whitney
The first occurrence of Cyonosaurus (Therapsida, Gorgonopsia) from the Luangwa Basin of Zambia
Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2444407
Arjan Mann & Christian A. Sidor
Arctops umulunshi, sp. nov. (Therapsida: Gorgonopsia) from the upper Madumabisa Mudstone Formation of Zambia, with new information on gorgonopsian postcranial anatomy Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2444405
Adam K. Huttenlocker, Claire Browning, Brandon R. Peecook, Roger M. H. Smith & Pia A. Viglietti
The stratigraphic record of the therocephalian Theriognathus (Synapsida) and its utility as a biostratigraphic index in Karoo-Aged basins Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2024.2441899
Brandon R. Peecook, Christian A. Sidor, Julia A. McIntosh, Pia A. Viglietti, Roger M. H. Smith, Neil J. Tabor, Christian F. Kammerer, Jacqueline K. Lungmus, Joseph Museba, Stephen Tolan, Megan R. Whitney & Kenneth D. Angielczyk
Successive assemblages of upper Permian vertebrates in the upper Madumabisa Mudstone Formation of the Luangwa Basin, Zambia Journal of Vertebrate Paleontology, 45(sup1). https://doi.org/10.1080/02724634.2025.2486065

Because of the sheer quantity of the papers in this memoir of the Journal of Vertebrate Palaeontolgy, I asked AI (ChatGPT 5) to summarise it:

What the special issue shows. A large, well-dated Permian record, across three African basins.
After ~15–17 years of fieldwork, the team synthesises thousands of fossils from the Ruhuhu (Tanzania), Luangwa and Mid-Zambezi (Zambia) basins into a coherent, late Permian picture (largely Wuchiapingian–early Changhsingian, ~256–252 Ma). The editors’ introduction and the University of Washington summary set the scope: 14 articles, >2,800 specimens, and faunas that can be compared directly with Karoo biozones. [14, 15]

New taxa and range extensions (multiple synapsid and reptile lineages).

Dicynodonts (herbivorous synapsids): new geikiid Aulacephalodon kapoliwacela (Luangwa), a new cryptodont Mdomowabata trilobops (Ruhuhu, Usili Fm.), and a large emydopoid Dicynodontoides kubwa (Usili Fm.). A separate phylogenetic paper on Lystrosauridae names additional Permian species (Euptychognathus kingae, Madumabisa opainion) and revises relationships leading into the iconic Triassic Lystrosaurus. Together these expand clade diversity and show key features were in place before the mass extinction. [16]
Gorgonopsians (sabre-toothed predators): first Luangwa record of Cyonosaurus and a new species, Arctops umulunshi; both clarify predator guilds and niche partitioning and help pin the upper Madumabisa Mudstone to the late Wuchiapingian. A histology paper on a Luangwa gorgonopsian adds life-history detail. [17]
Temnospondyl amphibians: first Paleozoic temnospondyl from Zambia, Rhineceps karibaensis (Mid-Zambezi), extending rhinesuchid geography and diversity prior to the end-Permian crise. [18]
Early reptiles:Amenoyengi mpunduensis, a diminutive moradisaurine captorhinid from Luangwa, ranks among the geologically youngest captorhinids, refining the group’s last appearances. [19]

Functional anatomy and ecology.

Postcranial anatomy of the cistecephalid Kembawacela kitchingi demonstrates forelimb specialisations and functional diversity among burrowing dicynodonts. [20]
Predator bone microstructure (gorgonopsian histology) informs growth and physiology within late Permian ecosystems. [21]

Biostratigraphy and correlation—tightening the timeline.

A review of the therocephalian Theriognathus refines its first/last appearances and recommends it as a reliable index fossil to correlate Ruhuhu (Usili Fm.) and Luangwa (upper Madumabisa Mudstone) to upper Cistecephalus–lower Daptocephalus zones, i.e., late Wuchiapingian (~256–253 Ma). [22]
Cyonosaurus in Luangwa independently supports a late Wuchiapingian age. [23]
A stratigraphic study recognises successive vertebrate assemblages within the upper Madumabisa, documenting turnover *within* the late Permian—before the terminal extinction—rather than a single mixed “flood” lag. [24]

Sedimentology and taphonomy—how the fossils accumulated.

The conglomerate-hosted bonebeds at the base of the Usili Formation record a tectonic and environmental shift (lacustrine → alluvial), with seasonal signals (hematite encrustations on bone; tree-ring seasonality). This is a process-rich, multi-event story, not a one-off catastrophe. [25]

Why this is a problem for creationism

The dates are the dates. Multiple, independent correlations (index taxa, cross-basin faunal matches) lock these beds into the Late Permian (≈256–252 Ma)-orders of magnitude older than a 6–10 kyr Young-Earth timeline. [23]
Transitional diversity is everywhere. The memoir documents stepwise anatomical change and branching within dicynodonts (including lineages ancestral/adjacent to Triassic Lystrosaurus), therocephalians, gorgonopsians, temnospondyls and early reptiles—exactly the graded pattern evolution predicts and creationist dogma says should not exist. [26]
Stratigraphic order, not slurry. Distinct, successive assemblages and refined first/last appearances contradict “Flood mixing” claims. The fossils appear where they should in the column, repeatedly and predictably, across basins. [24]
Consilience of evidence. Taxonomy, histology, sedimentology and taphonomy all tell the same story: long-lived ecosystems changing through time and space, then collapsing at the end-Permian mass extinction—hard to square with “intelligent design” and impossible under a recent-Earth chronology. [15]

When fourteen peer-reviewed studies from three African basins, spanning dozens of species and multiple lines of evidence, all converge on late-Permian ecosystems more than 250 million years old, denial isn’t an alternative explanation—it’s a refusal to look at the fossils.

Advertisement

Amazon