Feiko Miedema

336 posts

Feiko Miedema banner
Feiko Miedema

Feiko Miedema

@Feikosaur

Vertebrate Paleontologist, marine reptiles, mainly ichthyosaurs, ontogeny, prenatal development

Zurich, Switzerland Katılım Ocak 2022
366 Takip Edilen419 Takipçiler
Sabitlenmiş Tweet
Feiko Miedema
Feiko Miedema@Feikosaur·
Very happy to share our new paper! bmcecolevol.biomedcentral.com/articles/10.11… We re-evaluated ichthyosaur birth positions over their evolutionary history. Came to the conclusion that the classic tail-first birth is more derived than previously thought!
Feiko Miedema tweet mediaFeiko Miedema tweet media
English
9
140
497
45.8K
Feiko Miedema
Feiko Miedema@Feikosaur·
Last but not least: as notochord retention is a feature in all derived vertebrates, this method is potentially transferable to other groups!
English
0
0
2
43
Feiko Miedema
Feiko Miedema@Feikosaur·
2) Ichthyosaurs have an anterio-posterior developmental grade in their vertebral column, whereby anterior develops earlier. 3) Inferred stage in species with very few fetuses is corroborated by NCI. This will help majorly in staging ichthyosaur fetuses.
English
1
0
2
62
Feiko Miedema
Feiko Miedema@Feikosaur·
It is finally out! In this paper we show an easy way to stage ichthyosaur fetuses based on the relative size of their notochordal canal on their vertebrae (NCI). Important findings: NCI clearly separates fetal stage together with cranium royalsocietypublishing.org/rsos/article/1…
Feiko Miedema tweet media
English
1
7
36
1.1K
Feiko Miedema retweetledi
Stephan Spiekman
Stephan Spiekman@StephanSpiekman·
🦴Check out our new paper describing the internal anatomy of the long-necked tanysaurians, showing that bizarre inner vertebral anatomy is not restricted to dinosaurs and pterosaurs. This is part of the PhD work of Adam Rytel. Watch out for much more! doi.org/10.1093/zoolin…
English
0
24
94
4.7K
Aldo Benites-Palomino
Aldo Benites-Palomino@paleoAldo·
Its is done. I have finalised and submitted my doctoral dissertation: 5 chapters (4 published, one ready) and 5 appendices (4 papers coauthored and one side project to be submitted soon). Stay tune for the public defence. Till then, I have earned some vacations right?
Aldo Benites-Palomino tweet media
English
9
2
103
2.4K
Feiko Miedema
Feiko Miedema@Feikosaur·
This is a very good attempt at the ontogeny issue! Two questions: 1) How complete and undeformed do specimens have to be to exclude taphonomic bias in discrete non-variable characters? 2) Is the tooth count character transferable to amniotes with differing tooth implantation?
Dr. James G. Napoli@JGN_Paleo

Vertebrate paleontology has an ontogeny problem. I think I've solved it. NEW PREPRINT and THREAD 🧵 (link to preprint at the end) (Picture from Tetrapod Zoology, images owned by authors cited therein)

English
1
0
4
485
Feiko Miedema
Feiko Miedema@Feikosaur·
2) Carrying the more heavy fetal head towards the center of the maternal body during gestation may be beneficial to keep balance during swimming throughout the pregnancy (trim control).
English
0
0
13
303
Feiko Miedema
Feiko Miedema@Feikosaur·
In the paper we give two alternative hypotheses: 1) The shape of the fetus in fully marine whales and ichthyosaurs (large head, small pelvis, virtually no neck) makes pushing by the mother on the head more energetically advantageous
English
1
0
11
314

Keşfet

@SMNStuttgart @Val_Fisch @michela_johnson @JouveStphane1 @NCN_PL @paleoAldo @elonmusk @BarackObama