Comparative musculo-skeletal ontogeny of tetrapods

Current Research Project

Title / Titel: Comparative musculo-skeletal ontogeny of tetrapods

Summary / Zusammenfassung: The importance of evolutionary developmental biology (evo-devo) in bringing embryology to the evolutionary synthesis cannot be underestimated. However, the field is largely dominated by experimental approaches using model species and by molecular biology. More organismic and comparative approaches to study ontogeny are also experiencing a revival, addressing the old question of the impact of developmental studies in systematics. This kind of work is also benefiting from advances in experimental techniques and the incorporation of palaeontological data, and is in part inspired by the growing realization that the study of complex structures in time is fundamental to generate solid phylogenetic hypotheses based on morphological characters. This project aims at addressing this issue by studying heterochronies (changes in developmental timing) in the late development of selected Recent and fossil amniotes.

Examination of skeletal heterochronies in tetrapods are restricted to few taxa and have sampled either the skull or the postcranium. Already patterns were discovered, but they require testing with a wider sampling. The phylogenetic breadth examined in this project and the new methods employed would address questions such as: How conserved are ossification sequences among amniotes? Are heterochronic shifts connected to functional/ecological traits? How are these shifts related to morphological diversification?

The specific aims of this project can summarized as follows: (1) clear and stain and/or CT scan ontogenetic series obtained from Museum collections and experimental labs, including most major clades of mammals and turtles and representatives of most other major tetrapod clades; (2) produce the first comprehensive analysis of changes in developmental timing of the mammalian and turtle skeletons in a phylogenetic framework; (3) test the utility of developmental timing data in reconstructing evolutionary relationships; (4) Describe the growth patterns in selected reptilian taxa from the fossil site of Monte San Giorgio.

Publications / Publikationen

Wilson LAB, Sánchez-Villagra MR. 2010. Diversity trends and their ontogenetic basis: an exploration of allometric disparity in rodents. Proc. Roy. Soc. B. doi: 10.1098/rspb.2009.1958.

Richardson MK, Gobes S, Leeuwen A van, Poelman A, Pieau C, Sánchez-Villagra MR. 2009. Heterochrony in Limb Evolution: Developmental Mechanisms and Natural Selection. Journal of Experimental Zoology, Molecular and Developmental Evolution. 312B: 639-664. DOI: 10.1002/jez.b.21250.

Werneburg I, Sánchez-Villagra MR. 2009. Time of organogenesis support basal sauropsid position of turtles in the amniote tree of life. BMC Evolutionary Biology. 9:82 doi:10.1186/1471-2148-9-82.

Goswami A, V. Weisbecker V, Sánchez-Villagra MR. 2009. Developmental modularity and the marsupial-placental dichotomy. Journal of Experimental Zoology, Molecular and Developmental Evolution. 312B: 186-195.

Sánchez-Villagra MR, Müller H, Sheil CA, Scheyer TM, Nagashima H, Kuratani S. 2009. Skeletal Development in the Chinese soft-shelled turtle Pelodiscus sinensis (Reptilia: Testudines: Trionychidae). Journal of Morphology 270:1381–1399. DOI: 10.1002/jmor.10766.

Werneburg I, Hugi J, Müller J, Sánchez-Villagra MR. 2009. Embryogenesis and ossification of Emydura subglobosa (Testudines, Pleurodira, Chelidae) and patterns of turtle development. Developmental Dynamics. 238:2770-2786.

Wilson AB, Sánchez-Villagra MR. 2009. Heterochrony and Patterns of Cranial Suture Closure in Hystricognath Rodents. Journal of Anatomy 214:339-354.

Sánchez-Villagra MR, Anjali Goswami G, Weisbecker V, Mock O, Kuratani S. 2008. Conserved relative timing of cranial ossification patterns in early mammalian evolution. Evolution and Development. 10:519-530.

Asher RJ, Geisler JH, Sánchez-Villagra MR. 2008. Morphology, palaeontology, and placental mammal phylogeny. Systematic Biology. 57:311-317.

Weisbecker V, Goswami A, Wroe S, Sánchez-Villagra MR. 2008. Ossification heterochrony in the mammalian postcranial skeleton and the marsupial-placental dichotomy. Evolution. 62:2027-2041.

Scheyer TM, Brüllmann B, Sánchez-Villagra MR. 2008. The ontogeny of the shell in side-necked turtles, with emphasis on the homologies of costal and neural bones. Journal of Morphology 269:1008–1021.

Sánchez-Villagra MR, Ziermann JM, Olsson L. 2008. Limb chondrogenesis in Graptemys nigrinoda (Emydidae), with comments on the primary axis and the digital arch in turtles. Amphibia-Reptilia. 29:85-92.

Bininda-Emonds ORP, Jeffery JE, Sánchez-Villagra MR, Hanken J, Colbert M, Pieau C, Selwood L, Cate C t, Raynaud A, Osabutey CK, Richardson MK. 2007. Forelimb-hind limb developmental timing across tetrapods. BMC Evol. Biol. 7:182 (DOI:10.1186/1471-2148-7-182).

Sánchez-Villagra MR, Maier W. 2006. Homologies of the mammalian shoulder girdle – a response to Matsuoka et al. Evolution and Development 8:113-115.

Giannini N, Goswami A, Sánchez-Villagra MR. 2006. Development of integumentary structures in Rousettus amplexicaudatus (Mammalia: Chiroptera: Pteropodidae) during late-embryonic and fetal stages. Journal of Mammalogy 87(5), 993–1001.

Sánchez-Villagra MR, Maier W. 2003. Ontogenesis of the scapula in marsupial mammals, with special emphasis on perinatal stages of didelphids and remarks on the origin of the therian scapula. Journal of Morphology 258: 115-129.

Sánchez-Villagra MR. 2002. Comparative patterns of postcranial ontogeny in therian mammals: an analysis of relative timing of ossification events. Journal of Experimental Zoology: Molecular and Developmental Evolution 294:264-273.

Keywords / Suchbegriffe: Ontogeny, phylogeny, heterochrony, skeleton, muscle

Project Leadership and Contacts / Projektleitung und Kontakte

Prof Marcelo Sánchez (Project Leader)

m.sanchez@pim.uzh.ch

Funding Source(s) / Unterstützt durch: SNF (Personen- und Projektförderung), Others
SNF 3100AO-116013/1 (PI)Leverhulme Foundation, UK (co-PI; PI: Dr. R. Asher, Cambridge)

In Collaboration with / In Zusammenarbeit mit

Dr. Robert Asher (Cambridge University)	United Kingdom
Prof. Lennart Olsson (Universität Jena)	Germany
Dr. Johannes Müller (Museum für Naturkunde, Berlin)	Germany

Duration of Project / Projektdauer: Mar 2007 to Mar 2011