Kenneth De Baets

Illustration of a kakapo - a large, moss-green flightless parrot with an owl-like face - sitting on a person's arm with just the arm visible. It has a circular framing depicting little scribbles of ferns and conifer branches. Behind it is a light brown background with pale lineart of mossy tree trunks and branches of New Zealand's forests.

Sad news: the kakapo population is down to 237 after a female bird called Solstice died of an infection.

According to the Kakapo Recovery Facebook page, she had
• 8 clutches
• 24 eggs laid
• 13 fertile eggs
• 6 chicks hatched
• 4 living offspring
• 27 descendants

Mean shape from the modern human and chimpanzee model (SSM 2). (a) The (semi-)landmarks defined as predictors (red) and predicted (turquoise) in our models. (b) The anatomical region in our model used as a predictor (red) and the predicted region (turquoise).

📖Published📖

Torres-Tamayo introduce a novel method using statistical shape modelling (SSM) to predict missing skeletal morphology from partially preserved hominin pelvic remains 🦴

🌍 🧪

buff.ly/dBNVoxl

Ammonoid Paleopathology We herein review fossil examples of pathological phenomena and present a historical review, definition, and the taxonomic handling of such anomalies (forma aegra concept, symptom vs. syndrome). The described phenomena are separated in those with exogenic (injuries,...

21th chapter by Hoffmann & Keupp reviews the long #history of #ammonoid #paleopathology doi.org/10.1007/978-...

New reports fill #gaps in our #knowledge:
doi.org/10.1007/s125...
doi.org/10.7717/peer...
doi.org/10.4202/app....
doi.org/10.5710/AMGH...
doi.org/10.5194/fr-2...
doi.org/10.18261/let...

Parasites of Ammonoids Extant cephalopods are commonly infested by parasites making it plausible that ammonoids also had parasites. We review the fossil evidence of parasitic infestations in ammonoids, which, due to low preservation potential of soft-tissues in ammonoids and parasites, are...

20th chapter by De Baets et al. on #Parasites of #Ammonoids through #paleopathology: rdcu.be/eJqp7

Multiple new reports of parasite-induced #pathologies:
doi.org/10.4202/app....
doi.org/10.18261/let...
doi.org/10.5710/AMGH...

Identifying the culprits remains difficult:
doi.org/10.1007/978-...

Isotope Signature of Ammonoid Shells Geochemical analyses of ammonoid shells provide an independent and objective data set to evaluate life and habitat of the animal. This uniformitarian consideration, in combination with functional morphology and physical evidence for ecology or physiology, potentially...

19th chapter by Moriya on #Isotope Signature of #Ammonoid #Shells: rdcu.be/eJqoP

Their interpretation remains controversial today:
doi.org/10.1016/j.cr...
doi.org/10.1111/pala...

New approaches (doi.org/10.1017/pab....) and #modelling (doi.org/10.1007/s133...)
may however help in this endeavour.

Stable isotopes and predation marks shed new light on ammonoid habitat depth preferences - Scientific Reports Scientific Reports - Stable isotopes and predation marks shed new light on ammonoid habitat depth preferences

18th chapter by Lukeneder constrained #Ammonoid #Habitats and #Life History: rdcu.be/eJqnW

This remains tricky and only doable with a multi-proxy approaches combining #morphology, #geochemistry, #modelling and facies analysis:
doi.org/10.1038/s415...
doi.org/10.1080/0311...
doi.org/10.1007/978-...

17th chapter by Naglik et al. focuses on #Ammonoid #Locomotion: rdcu.be/eJqhf

Latest studies use #biomimetic models (doi.org/10.1093/iob/...
; doi.org/10.1038/s415...) or #Computational fluid dynamics (doi.org/10.26879/956).

#tradeoffs are key: doi.org/10.4202/app....
doi.org/10.1017/pab....

Ammonoid Buoyancy The buoyancy of ammonoids is one of the most controversial issues of ammonoid paleobiology. This chapter gives a short historical review about attempts made to clarify the potential function of the cephalopod chambered shell (phragmocone) and ammonoid life habits...

16th chapter by Hoffmann et al. reviews #Ammonoid #Buoyancy: rdcu.be/eJqeH

New methods show even the oldest and oddest ammonoids neutral buoyancy and #life orientation: doi.org/10.1111/let.... doi.org/10.1016/j.ge...
doi.org/10.1371/jour...
doi.org/10.1038/s415...
doi.org/10.1017/pab....

15th chapter by Doguzhaeva & Mutvei explored Additional External #Shell Layers Indicative of “Endocochleate Experiments” in Some #Ammonoids: rdcu.be/eJm0q

Covered shell remains poorly explored: doi.org/10.1080/1103...

Support for partial mantle #cover at best: dx.doi.org/10.3140/bull.geosci.1522

The Body Chamber Length Variations and Muscle and Mantle Attachments in Ammonoids The varying body chamber lengths and the different attachment of muscles and mantle to conch wall belong to the major adaptations to their diverse modes of locomotion. Therefore, these traits are indirect indicators of different life styles. The sparse record of...

14th chapter by Doguzhaeva & Mapes on The Body Chamber Length Variations and #Muscle and #Mantle Attachments in #Ammonoids: rdcu.be/eJmJf

Scars suggest powerful retractor muscles (doi.org/10.1093/moll...) but their #function remains debated (doi.org/10.1130/G499...; doi.org/10.1130/G495...)

"...although analyses of extant phylogenies can estimate extinction rates and even suggest mass extinctions, they cannot imply trilobites ever existed or that sphenodonts (now represented only by the tuatara) were once as diverse as lepidosaurs (lizards and snakes)." #FossilFriday 🧪

Additional new #fossil #cocoon discoveries further underline a pre-Mesozoic #clitellata origin (doi.org/10.1017/jpa....) running counter to most evidence so tar (doi.org/10.1017/pab....).

Report on ammonoid soft tissue remains revealed by computed tomography - Swiss Journal of Palaeontology Findings of ammonoid soft tissues are extremely rare compared to the rich fossil record of ammonoid conchs ranging from the Late Devonian to the Cretaceous/Paleogene boundary. Here, we apply the computed-tomography approach to detect ammonoid soft tissue remains in well-preserved fossils from the Early Cretaceous (early Albian) of NE-Germany of Proleymeriella. The ammonites were found in glauconitic–phosphatic sandstone boulders. Analyses of the high-resolution Ct-data revealed the presence of cameral sheets, the siphuncular tube wall, and the siphuncle itself. The siphuncle is a long, segmented soft tissue that begins at the rear end of the body chamber and comprises blood vessels. Chemical analyses using energy-dispersive spectroscopy (EDS) showed that all preserved soft tissues were phosphatized and are now composed of fluorapatite. The same holds true for preserved shell remains that locally show the nacreous microstructure. We provide a short description of these soft tissue remains and briefly discuss the taphonomic pathway.

13th chapter by Tanabe et al. shows Soft-Part #Anatomy of the #Siphuncle in #Ammonoids: rdcu.be/eJhAM

The structure for #buoyancy regulation is rarely preserved but #ComputedTomography reveals key details: rdcu.be/eJhAB

Also multiple new findings:
doi.org/10.2110/palo...
doi.org/10.2110/palo...

12th chapter by Klug & Lehmann reviews #Soft Part #Anatomy of #Ammonoids: rdcu.be/eJgOJ

New studies underline that rare #exceptionally #preserved specimens (doi.org/10.1130/G495...; rdcu.be/eJgSe) as well as actualistic comparisons (rdcu.be/eJgHQ) to reconstructing these animals.

Key innovations in Mesozoic ammonoids: the multicuspidate radula and the calcified aptychus A nearly complete radula with seven elements per row preserved inside of an isolated, bivalved, calcitic lower jaw (= aptychus) of the Late Jurassic ammonite Aspidoceras is described from the Fossill...

11th chapter by Kruta et al. reviews the #Ammonoid #Radula: rdcu.be/eJgIw

These #feeding structures date back to the #Cambrian:
doi.org/10.3140/bull...

Its modification led to calcified lower #jaws in derived ammonoids: doi.org/10.1111/pala...

Not all #chitinous hooks are radular: rdcu.be/eJgHQ

Giant DNA viruses encode a hallmark translation initiation complex of eukaryotic life In contrast to living organisms, viruses were long thought to lack protein synthesis machinery and instead depend on host factors to translate viral transcripts. Here, we discover that giant DNA virus...

Historically, viruses were thought to primarily use host cell's translational machinery. New work from @harvardcellbio.bsky.social faculty Amy Lee reveals that a giant DNA virus encodes its own IF4F initiation complex, suggesting an unexpected evolutionary innovation. www.biorxiv.org/content/10.1...

#Marine #origins and #freshwater #radiations of the otophysan fishes: dx.doi.org/10.1126/science.adr4494

I would be nice to have a Time Machine but I do not want to go back to medieval times complete with rich tyrants and crusades not in the past or the future

The @EUCommission would like to hear your views on the governance and sustainability of critical open source software. The survey closes October 5th.

https://ec.europa.eu/eusurvey/runner/FOSSEPS_Governance_and_Sustainability_Survey

#OpenSource #Governance #Sustainability

Fischsterben bei Rostock: Seuche ausgeschlossen - Angeln wieder möglich Untersuchungen der verendeten Fische haben weder Schadstoffe noch Verletzungen gefunden. Auch eine Seuche wird mittlerweile ausgeschlossen. Laut Umweltministerium gilt Sauerstoffmangel als wahrscheinl...

Die #Ostsee stirbt, man kann es nicht anders sagen.

Und Hauptursache ist nicht der Klimawandel 🌡️, nicht die Munitionsbelastung 💣, nicht die Fischerei 🐟...
Das kommt alles nur noch obendrauf auf die Hauptursache:
👉 #Eutrophierung mit Stickstoff & Phosphor ☠️

Ammonoid Buccal Mass and Jaw Apparatus Current knowledge on the ammonoid buccal mass and jaw apparatus is synthesized based on in situ fossil records from 109 genera that are distributed in 30 superfamilies of 8 suborders of Devonian to Cretaceous age. As in those of modern cephalopods, the jaw apparatus...

10th chapter by Tanabe et al. reviews #Ammonoid #Buccal #Mass and #Jaw #Apparatus: doi.org/10.1007/978-...

New jaw studies implies that:
chitinous mandibles were present at the origin of the whole clade: doi.org/10.1111/pala...

#squid radiation before ammonoid #extinction: doi.org/10.1126/scie...

New paper!

"Fossil tip-dating reveals novelties on evolutionary and diversification trends in three Late Ordovician brachiopod genera (Atrypida, Anazygidae)" Yay for brachiopods! 🧪

Goniatites sphaericus (Sowerby, 1814), the archetype of Palaeozoic ammonoids: a case of decreasing phenotypic variation through ontogeny - PalZ The Late Viséan (Early Carboniferous) ammonoid species Goniatites sphaericus (Sowerby, 1814) is revised with the use of the type material. With respect to conch morphology, suture line and particularly shell ornament, it is regarded as a senior synonym of the species Goniatites fimbriatus (Foord and Crick, 1897) and must therefore be re-established as an important index fossil for the ammonoid stratigraphy of the Rhenohercynian and Subvariscan shelves. The Goniatites fimbriatus Zone has been re-named Goniatites sphaericus Zone on this basis. The study of ontogenetic changes in the conch parameters shows that intraspecific variation occurs within a wide range. In the whorl profile, variation is very high in small juveniles, while in the coiling rate, intermediate growth stages are more strongly affected.

9th chapter by De Baets et al. reviews #Ammonoid #Intraspecific #Variability: doi.org/10.1007/978-...

New studies corroborate high variation in early-middle stages: doi.org/10.1007/s125...
doi.org/10.1017/pab....
or important ecophenotypic variation:
doi.org/10.1017/pab....
doi.org/10.1206/3922.1

From pristine aragonite to blocky calcite: Exceptional preservation and diagenesis of cephalopod nacre in porous Cretaceous limestones Aragonite (along with calcite) is one of the most common polymorphs of the crystalline calcium carbonate that forms the skeletal structures of organisms, but it has relatively low preservation potenti...

8th chapter by Kulicki et al. reviews Ammonoid Shell Microstructure: doi.org/10.1007/978-...

New studies show that microstructural differences between shell layers influence their susceptibility to dissolution, recrystallization, or preservation:
doi.org/10.1371/jour...
doi.org/10.1111/pala...

The first #leech body #fossil predates estimated hirudinidan origins by 200 million years

peerj.com/articles/199...

@peerj.bsky.social #Annelida

Rare fossil reveals ancient leeches weren’t bloodsuckers A newly described fossil reveals that leeches are at least 200 million years older than scientists previously thought, and that their earliest ancestors may have feasted not on blood, but on smaller m...

news.ucr.edu/articles/202...

Look, I'm just some guy, but I think I have a better than 57.2% rate of successfully editing a spreadsheet.

Mature Modifications and Sexual Dimorphism Most ammonoids display a distinctly different morphology when they are adults or subadults. Depending on the taxon, these mature modifications may comprise changes in coiling, changes in ornamentation, and conspicuous changes of the terminal aperture. These mature...

7th chapter by Klug et al. on Mature Modifications and Sexual Dimorphism - common in Mesozoic ammonoids: doi.org/10.1007/978-...

New studies support it in many taxa
doi.org/10.4202/app....
doi.org/10.4202/app....
doi.org/10.1017/pab....

One documents intersexuality:
doi.org/10.1186/s128...

Theoretical Modelling of the Molluscan Shell: What has been Learned From the Comparison Among Molluscan Taxa? The molluscan shell has been the subject of extensive theoretical work for over a century. From geometrical models to mechano-chemical models, a wide range of models exist that highlight the principles underlying coiling and the ornamentation in molluscan shells....

6th chapter by Urdy on #Theoretical #Modelling of the #Molluscan #Shell: What has been Learned From the Comparison Among Molluscan Taxa? doi.org/10.1007/978-...

Ammonoids keep playing a prominent role in modelling shells: doi.org/10.1073/pnas... doi.org/10.1002/ece3... doi.org/10.1002/jez....

First direct evidence of ammonoid ovoviviparity Ammonoids had high evolutionary rates and diversity throughout their entire history and played an important role in the high-resolution sub-division of the Mesozoic, but much of their palaeobiology re...

5th chapter by me, Landman & Tanabe summarised our understanding of #ammonoid #embryonic #development: doi.org/10.1007/978-...

Spectacular discoveries further constrain their #reproductive strategies: doi.org/10.1111/let....
doi.org/10.7717/peer...
dx.doi.org/10.4202/app....
doi.org/10.1017/pab....