Vergleichende Entwicklungsgeschichte — A Festschrift on the occasion of the 80th birthday of Prof. Dr. Wolfgang Maier, Tübingen

Abstract

Following the traditional and holistic concept of Vergleichende Entwicklungsgeschichte, Wolfgang Maier studied different aspects of vertebrate morphology, including dentition, the locomotor apparatus, nasal and ear regions. His work comprises investigations on pre- to postnatal stages of extant species as well as fossils and is mainly based on histological serial sections, but also on µCT data in recent years. This resulted in an integrative research agenda on the evolutionary biology of mammals and other vertebrates. Most of his studies are designed around the interrelationship of ontogenetic and functional adaptations and evolutionary transformations. The present collection in Vertebrate Zoology collates a series of research articles related to and in honor of Wolfgang Maier’s work. Invited colleagues of Maier provide current insights to their own research, in many cases inspired by his scholarship, ranging from mammalian to reptilian and fish comparative anatomy. In total, this volume contains 19 publications. They apply modern and traditional techniques to investigate the diversity of biological form. In so doing, they integrate traditional conceptual frameworks from the earliest days of morphological research more than two centuries ago.

Evolution of the temporal skull openings in land vertebrates: A hypothetical framework on the basis of biomechanics

“…Most turtles, as another example, have elongated supraoccipital and squamosal crests permitting long muscle fibers to develop (Schumacher, 1973; Werneburg, 2011). These, however, are merely evolved to circumvent the large otical bar (cryptodires) or pterygoid flange (pleurodires), which restrict space in the adductor chamber (Werneburg, 2013a) and are related to the akinetic turtle skull (Werneburg & Maier, 2019). Under this condition, jaw muscle force can be maintained (Ferreira et al, 2020) by forming a largely feathered jaw musculature with many muscle fibers inserting to sheets of the jaw adductor tendon (Schumacher, 1956a, 1956b; Werneburg, 2013b).…”

“…the head is passively swept to the right of the animal (curved arrow) the head is actively pulled to the left side (curved arrow), the transversal bite forces (Fbt) act in the opposite direction of mass intertia (Fi) anterior + posterior FbtA akinetic turtle skull (Werneburg & Maier, 2019). Under this condition, jaw muscle force can be maintained (Ferreira et al, 2020) by forming a largely feathered jaw musculature with many muscle fibers inserting to sheets of the jaw adductor tendon (Schumacher, 1956a(Schumacher, , 1956bWerneburg, 2013b).…”

Chondrocranial anatomy of Testudo hermanni (Testudinidae, Testudines) with a comparison to other turtles

“…gigantea (Danielson & Sheil, 2017;Fuchs, 1915;Gerlach, 2012;Kunkel, 1912;Kuratani, 1999;Leicht et al, 2023;Rieppel, 1976;Sánchez-Villagra et al, 2009;Sheil, 2003Sheil, , 2013Sheil & Greenbaum, 2005;Tokita et al, 2021;Tulenko & Sheil, 2007). The ascending process ossifies as the epipterygoid during the cranial development and forms part of the lateral braincase wall in cryptodires (Clark et al, 1993;Werneburg & Maier, 2019). Pleurodire turtles lack an ascending process and do not form an epipterygoid, as…”

The topological organization of the turtle cranium is constrained and conserved over long evolutionary timescales

“…Non‐shelled stem‐turtles are generally older, and possibly date back to the Permian Eunotosaurus africanus (Bever et al, 2015). Turtles are unique in regard to their highly derived body plan, which includes the bony shell that encapsulates much of the body (e.g., Lyson et al, 2013; Zangerl, 1969) and a highly derived skull anatomy (e.g., Ferreira et al, 2020; Gaffney, 1979, 1990; Rabi et al, 2013; Sterli et al, 2010; Sterli & Joyce, 2007), as well as the ability to retract their necks through either a side‐necked or hidden‐necked mode of retraction (Abel & Werneburg, 2021; Ferreira & Werneburg, 2019; Joyce, 2017; Młynarski, 1976; Werneburg, 2015; Werneburg & Maier, 2019). Testudines have a near‐global distribution and inhabit terrestrial, freshwater and marine habitats (Ernst et al, 1989; Gaffney, 1979), and their fossil record demonstrates numerous ecological transitions from aquatic environments to terrestrial ones and vice versa (Anquetin et al, 2015; Claude et al, 2003; Evers & Benson, 2019; Ferreira et al, 2015).…”

“…Evolutionary changes in testudinatan skulls have been well documented due to a good fossil record of stem turtles dating back to origin of Testudinata in the Late Triassic (e.g., Anquetin, 2010; Gaffney, 1990; Sterli, 2008; Sterli et al, 2007; Sterli & Joyce, 2007). Turtles possess many apomorphies (derived traits), including akinesis by fusion of intracranial joints (e.g., Ferreira et al, 2020; Rabi et al, 2013), loss of teeth (e.g., Gaffney et al, 1987), and anapsid skulls without temporal fenestration (e.g., Foth & Joyce, 2016; Werneburg & Maier, 2019). Some of these evolutionary novelties have been well documented in the fossil record (e.g., Rabi et al, 2013), whereas others, such as the evolution of the anapsid skull composition, is less well understood and depends on the phylogenetic placement of key taxa as non‐testudinatan stem turtles, such as Eunotosaurus africanus (e.g., see Bever et al, 2015 vs. Simões et al, 2022 or Wolniewicz et al, 2023).…”