Urumaco and Venezuelan Paleontology: The Fossil Record of the Northern Neotropics. Life of the Past. Edited by Marcelo R. Sánchez‐Villagra, Orangel A. Aguilera, and Alfredo A. Carlini. Bloomington (Indiana): Indiana University Press. $49.95. x + 286 p. + 8 pl.; ill.; index. ISBN: 978‐0‐253‐35476‐1. 2010.

2011 ◽  
Vol 86 (4) ◽  
pp. 338-338
Author(s):  
K. E. Beth Townsend ◽  
Aryeh Grossman
2000 ◽  
Vol 6 ◽  
pp. 171-182 ◽  
Author(s):  
Ben A. LePage ◽  
Hermann W. Pfefferkorn

When one hears the term “ground cover,” one immediately thinks of “grasses.” This perception is so deep-seated that paleobotanists even have been overheard to proclaim that “there was no ground cover before grasses.” Today grasses are so predominant in many environments that this perception is perpetuated easily. On the other hand, it is difficult to imagine the absence or lack of ground cover prior to the mid-Tertiary. We tested the hypothesis that different forms of ground cover existed in the past against examples from the Recent and the fossil record (Table 1). The Recent data were obtained from a large number of sources including those in the ecological, horticultural, and microbiological literature. Other data were derived from our knowledge of Precambrian life, sedimentology and paleosols, and the plant fossil record, especially in situ floras and fossil “monocultures.” Some of the data are original observations, but many others are from the literature. A detailed account of these results will be presented elsewhere (Pfefferkorn and LePage, in preparation).


PalZ ◽  
2021 ◽  
Author(s):  
Carolin Haug ◽  
Joachim T. Haug

AbstractWhip spiders (Amblypygi), as their name suggests, resemble spiders (Araneae) in some aspects, but differ from them by their heart-shaped (prosomal) dorsal shield, their prominent grasping pedipalps, and their subsequent elongate pair of feeler appendages. The oldest possible occurrences of whip spiders, represented by cuticle fragments, date back to the Devonian (c. 385 mya), but (almost) complete fossils are known from the Carboniferous (c. 300 mya) onwards. The fossils include specimens preserved on slabs or in nodules (Carboniferous, Cretaceous) as well as specimens preserved in amber (Cretaceous, Eocene, Miocene). We review here all fossil whip spider specimens, figure most of them as interpretative drawings or with high-quality photographs including 3D imaging (stereo images) to make the three-dimensional relief of the specimens visible. Furthermore, we amend the list by two new specimens (resulting in 37 in total). The fossil specimens as well as modern whip spiders were measured to analyse possible changes in morphology over time. In general, the shield appears to have become relatively broader and the pedipalps and walking appendages have become more elongate over geological time. The morphological details are discussed in an evolutionary framework and in comparison with results from earlier studies.


2011 ◽  
Vol 1 (1) ◽  
pp. e1 ◽  
Author(s):  
Tanya M. Smith ◽  
Anne-Marie Bacon ◽  
Fabrice Demeter ◽  
Ottmar Kullmer ◽  
Kim Thuy Nguyen ◽  
...  

Orangutans (Pongo) are the only great ape genus with a substantial Pleistocene and Holocene fossil record, demonstrating a much larger geographic range than extant populations. In addition to having an extensive fossil record, Pongo shows several convergent morphological similarities with Homo, including a trend of dental reduction during the past million years. While studies have documented variation in dental tissue proportions among species of Homo, little is known about variation in enamel thickness within fossil orangutans. Here we assess dental tissue proportions, including conventional enamel thickness indices, in a large sample of fossil orangutan postcanine teeth from mainland Asia and Indonesia. We find few differences between regions, except for significantly lower average enamel thickness (AET) values in Indonesian mandibular first molars. Differences between fossil and extant orangutans are more marked, with fossil Pongo showing higher AET in most postcanine teeth. These differences are significant for maxillary and mandibular first molars. Fossil orangutans show higher AET than extant Pongo due to greater enamel cap areas, which exceed increases in enamel-dentine junction length (due to geometric scaling of areas and lengths for the AET index calculation). We also find greater dentine areas in fossil orangutans, but relative enamel thickness indices do not differ between fossil and extant taxa. When changes in dental tissue proportions between fossil and extant orangutans are compared with fossil and recent Homo sapiens, Pongo appears to show isometric reduction in enamel and dentine, while crown reduction in H. sapiens appears to be due to preferential loss of dentine. Disparate selective pressures or developmental constraints may underlie these patterns. Finally, the finding of moderately thick molar enamel in fossil orangutans may represent an additional convergent dental similarity with Homo erectus, complicating attempts to distinguish these taxa in mixed Asian faunas. 


2001 ◽  
Vol 75 (6) ◽  
pp. 1119-1127 ◽  
Author(s):  
Jay A. Schneider

Over the past 75 years, the higher-level taxonomy of bivalves has received less attention than that of their fellow molluscs, gastropods. The publication of the bivalve volumes of the Treatise on Invertebrate Paleontology in 1969 was not followed by an explosion of study into the evolution of bivalves; rather, with only one or two exceptions, bivalve workers were noticeably absent from the cladistic and molecular revolutions that were taking place during the 1970s and 1980s, even as gastropods received considerable attention. Over the past ten years, cladistics and molecular systematics have begun to be applied to solve problems of bivalve evolutionary biology. These studies, most of which have been undertaken by paleontologists, have halted the stagnation in bivalve systematics. Bivalve systematics looks to have an exciting future, as the excellent fossil record of the Bivalvia will be used in conjunction with cladistics and molecular systematics to solve problems in not just bivalve evolution but evolutionary biology in general.


2004 ◽  
Vol 1 (3) ◽  
pp. 387-398
Author(s):  
DAVID D. HALL

George M. Marsden, Jonathan Edwards: A Life (New Haven, CT: Yale University Press, 2003)Robert E. Brown, Jonathan Edwards and the Bible (Bloomington: Indiana University Press, 2002)Avihu Zakai, Jonathan Edwards's Philosophy of History: The Re-enchantment of the World in the Age of Enlightenment (Princeton, NJ: Princeton University Press, 2003)Amy Plantinga Pauw, “The Supreme Harmony of All”: The Trinitarian Theology of Jonathan Edwards (Grand Rapids, MI: Eerdmans, 2002)We play tricks on the past, but the past also plays tricks on us. We try to fool the past by reconstructing it in our own image, imposing order and significance on the untidy sources we depend upon. The trick the past plays on us is to remain defiantly strange, ever able to expose what it is that our gestures of sympathetic reconstruction have altered, ignored, or suppressed.


Zootaxa ◽  
2016 ◽  
Vol 4200 (2) ◽  
pp. 327 ◽  
Author(s):  
PEDRO S. R. ROMANO

Pelomedusoides is the most diverse clade of side-necked turtles and there is an extensive fossil record (de Broin, 1988; Lapparent de Broin, 2000; Gaffney et al., 2006, 2011) that dates back at least to the Barremian (Lower Cretaceous) (Romano et al., 2014). Its large fossil record evidences a greater diversity in the past, particularly at the end of the Mesozoic, and exhibits a good sampling of species that are represented by skull material (Gaffney et al., 2006, 2011). As a consequence, the most complete and recent phylogenetic hypotheses for this clade (e.g. Romano et al., 2014; Cadena, 2015) are based on matrices comprising a great amount of cranial characters derived largely from Gaffney et al. (2006, 2011). In addition, it is well established that shell characters show a lot of phenotypic plasticity, even in the fossil species (Romano, 2008; Gaffney et al., 2006, 2011). In most cases it consequently is not justified to rely on “diagnostic features” of poorly informative shell-only material for describing a new species. Because of that, most authors remark new morphotypes in the literature when such aberrant specimens are recovered, but do not make any nomenclatural act by proposing a new yet poorly supported species (e.g. Romano et al., 2013; Ferreira & Langer, 2013; Menegazzo et al., 2015). Unfortunately, such a supposedly new bothremydid turtle (Pleurodira: Bothremydidae) from the Early Paleocene of Brazil was recently described based on poorly diagnostic remains (Carvalho et al., 2016; hereafter CGB, for the authors initials) and a correction of this unfounded nomenclatural act is required. In addition I present some comments on shell only material from Brazil in order to guide splitter-taxonomists to stop describing poorly preserved fossil specimens as new species. 


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