Symbiosis [1], understood as prolonged interspecific association, is as ancient as the eukaryotic... more Symbiosis [1], understood as prolonged interspecific association, is as ancient as the eukaryotic cell [2, 3]. A variety of such associations have been reported in the continental fossil record, albeit sporadically. As for mites, which as a group have been present since the Devonian (ca. 390 mya) [4, 5] and are involved in a tremendous variety of modern-day symbioses, reported associations are limited to a few amber-preserved cases [6-11], with the earliest instance in the Cretaceous (ca. 85 mya) [11]. As a consequence, the antiquity and origin of associations involving small-sized mites and larger animals are poorly understood. Here we report, recovered from the Carboniferous Xiaheyan locality (ca. 320 mya), an oribatid mite located on the thorax of an extinct relative of grasshoppers, crickets, and katydids [12]. The mite was investigated using several methods, including phase-contrast tomography. The detailed morphological data allowed the placement of the mite in a new family wi...
Add to : A Giant Chelonioid Turtle from the Late Cretaceous of Morocco with a Suction Feeding App... more Add to : A Giant Chelonioid Turtle from the Late Cretaceous of Morocco with a Suction Feeding Apparatus Unique among Tetrapods, PLoS ONE 8(7): e63586
Bone microanatomy appears to track changes in various physiological or ecological properties of t... more Bone microanatomy appears to track changes in various physiological or ecological properties of the individual or the taxon. Analyses of sections of the tibia of 99 taxa show a highly significant (P ≤ 0.005) relationship between long-bone microanatomy and habitat. Randomization tests reveal a highly significant (P ≤ 0.005) phylogenetic signal on several compactness profile parameters and lifestyle. Discriminant analyses yield an inference model which has a success rate of 63% when lifestyle is coded into three states (aquatic, amphibious and terrestrial) or 83% for a binary model (aquatic vs. amphibious to terrestrial). Lifestyle is inferred to have been terrestrial for the stem-tetrapod Discosauriscus (Early Permian), the basal synapsid Dimetrodon (Early Permian), the dicynodont therapsid Dicynodon (Late Permian), an unindentified gorgonopsian (Late Permian); the parareptile Pareiasaurus (Middle or Late Permian) is modelled as being aquatic, but was more likely amphibious.
Symbiosis [1], understood as prolonged interspecific association, is as ancient as the eukaryotic... more Symbiosis [1], understood as prolonged interspecific association, is as ancient as the eukaryotic cell [2, 3]. A variety of such associations have been reported in the continental fossil record, albeit sporadically. As for mites, which as a group have been present since the Devonian (ca. 390 mya) [4, 5] and are involved in a tremendous variety of modern-day symbioses, reported associations are limited to a few amber-preserved cases [6-11], with the earliest instance in the Cretaceous (ca. 85 mya) [11]. As a consequence, the antiquity and origin of associations involving small-sized mites and larger animals are poorly understood. Here we report, recovered from the Carboniferous Xiaheyan locality (ca. 320 mya), an oribatid mite located on the thorax of an extinct relative of grasshoppers, crickets, and katydids [12]. The mite was investigated using several methods, including phase-contrast tomography. The detailed morphological data allowed the placement of the mite in a new family wi...
Add to : A Giant Chelonioid Turtle from the Late Cretaceous of Morocco with a Suction Feeding App... more Add to : A Giant Chelonioid Turtle from the Late Cretaceous of Morocco with a Suction Feeding Apparatus Unique among Tetrapods, PLoS ONE 8(7): e63586
Bone microanatomy appears to track changes in various physiological or ecological properties of t... more Bone microanatomy appears to track changes in various physiological or ecological properties of the individual or the taxon. Analyses of sections of the tibia of 99 taxa show a highly significant (P ≤ 0.005) relationship between long-bone microanatomy and habitat. Randomization tests reveal a highly significant (P ≤ 0.005) phylogenetic signal on several compactness profile parameters and lifestyle. Discriminant analyses yield an inference model which has a success rate of 63% when lifestyle is coded into three states (aquatic, amphibious and terrestrial) or 83% for a binary model (aquatic vs. amphibious to terrestrial). Lifestyle is inferred to have been terrestrial for the stem-tetrapod Discosauriscus (Early Permian), the basal synapsid Dimetrodon (Early Permian), the dicynodont therapsid Dicynodon (Late Permian), an unindentified gorgonopsian (Late Permian); the parareptile Pareiasaurus (Middle or Late Permian) is modelled as being aquatic, but was more likely amphibious.
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Papers by damien germain