Patterns of postnatal development in skulls of lynxes, genusLynx (Mammalia: Carnivora)

Abstract

Studies on ossification patterns and other ontogenetic events associated with postnatal cranial growth of wild felids are scarce. An analysis of developmental processes undergone by several cranial structures (presphenoidal and sphenooccipital synchondroses, temporal and sagittal crests, and deciduous and permanent teeth) during postnatal growth has been conducted on a sample of 336 specimens belonging to the four Recent species of lynxes (Lynx pardinus, Lynx lynx, Lynx rufus, and Lynx canadensis). Age has been estimated based on tooth replacement, skull size, and by counting the annual lines of cementum growth. Comparison of the results obtained for each of the four species reveal (1) a single pattern for both tooth replacement and ossification of the sphenooccipital synchondrosis, (2) two ossification patterns for the presphenoidal synchondrosis, (3) a common pattern for development of temporal ridges and sagittal crest showing different degrees of morphological expression, and (4) evidence suggesting the involvement of a heterochronic process, neoteny, in the morphological differentiation of several populations and species of the genus Lynx. These data also support the hypothesis that processes involved in the replacement of carnassials are based on functional requirements. © 1996 Wiley‐Liss, Inc.

Ontogeny of the Early Triassic Cynodont Thrinaxodon liorhinus (Therapsida): Cranial Morphology

“…In some of the mammals that develop sagittal crests, the cranial vault is smooth at the early juvenile stage, and during ontogeny temporal ridges (5temporal lines or parasagittal ridges) develop on either side of the midline (Garcia-Perea, 1996;Holbrook, 2002). These ridges then migrate medially and dorsally to form a sagittal table, or if the ridges coalesce, they form a sagittal crest (Holbrook, 2002).…”

A quantitative approach to the cranial ontogeny of the puma

“…However, the morphometric changes that occur in the skull of felids during the ontogeny are incompletely understood because the scope of the available studies is limited and few species have been studied in a morphological and/or morphometric context to date. Such species include Panthera onca (Stehlik 1971;Slaughter et al 1974), P. pardus (Stander 1997), Leopardus wiedii (Volf 1972;Fagen and Wiley 1978;Petersen and Petersen 1978), Lynx (Crowe 1975;Johnson et al 1981;Jackson et al 1988;García-Perea 1996), Acinonyx jubatus (Broom 1949;Caro 1994), Caracal caracal (Stuart and Stuart 1985) and Puma concolor (Gay and Best 1996;Shaw et al 2007;Segura and Flores 2009). However, these studies focused either on age estimation, functional analysis, or morphological description, including qualitative approaches to the ontogeny of some extant felids and felid-like fossils.…”

The origin of the critically endangered Iberian lynx: Speciation, diet and adaptive changes

“…Comparisons-Two of the features described: the separation of the temporal lines, which merge in the caudal part of the cranium, and the confluence in the same cavity of the lacerum posterius and anterior condyloid foramina, are clear characters of Lynx pardinus (Van den Brink, 1971; García-Perea et al, 1985;García-Perea, 1996;Larivi ere and Walton, 1997). The latter character is especially highly diagnostic, allowing one to distinguish reliably between the living Iberian and Eurasian lynxes (Larivi ere and Walton, 1997).…”

“…Regarding morphometric data, if the length of the sagittal crest in IPS 4170 is even shorter than in the extant Lynx pardinus (data in García-Perea, 1996), the width and the length of the temporal lines, depicting a clear lyre-shaped surface on the cranial roof, are higher than in extant specimens of Lynx pardinus (data in García-Perea et al, 1985). However, other measurements such as the mastoid and postorbital widths, are slightly out of the Lynx pardinus range, being comparable with the cranium of Lynx issiodorensis valdarnensis from Pantalla and Olivola (Cherin et al, 2013) and suggesting that this specimen could represent one of the earliest forms of Lynx pardinus.…”

“…As suggested by García-Perea (1996), the marked reduction of the length and height of the sagittal crest in Lynx pardinus, could be related to a lower development of the temporalis, the strongest and largest muscle of the head, related with mastication (Miller et al, 1964;De Iuliis and Puler a, 2006). This bipennate muscle inserts on the mandible, originating from the temporal fossa, an area situated on the caudal cranial roof, bounded anteriorly by the orbital ligament and the external frontal crest, laterally by the zygomatic arch, caudally by the dorsal nuchal crest and medially by the external sagittal crest or temporal line (Miller et al, 1964;Evans and de Lahunta, 2013).…”