bluuebunny/crossref_metadata_2025 huggingface dataset:
Plankton ecology and the Proterozoic-Phanerozoic transition
Authors: Butterfield Nicholas J.
Published: July 2016

Most modern marine ecology is ultimately based on unicellular phytoplankton, yet most large animals are unable to graze directly on even relatively large net phytoplankton; the repackaging effected by herbivorous mesozooplankton thus represents a key link in marine metazoan food chains. Despite the deep taphonomic biases affecting plankton fossilization, there is a clear record of phytoplankton from at least 1800 m.y ago. Proterozoic plankton are represented by small-to medium-sized sphaeromorphic acritarchs and probably do not include many/most of the unusually large acritarchs that characterize the Neoproterozoic. The first significant shift in phytoplankton diversity was therefore the rapid radiation of small acanthomorphic acritarchs in the Early Cambrian. The coincidence of phytoplankton diversification with the Cambrian radiation of large animals points compellingly to an ecological linkage between the two, particularly in light of recently discovered filter-feeding mesozooplankton in the Early Cambrian. The introduction of planktic filter feeders would have established the second tier of the Eltonian pyramid, potentially setting off the “self-propagating mutual feedback system of diversification” now recognized as the Cambrian explosion (Stanley 1973, 1976).

By consuming significant percentages of net phytoplankton and suspending it as animal biomass and non-aggregating fecal pellets, mesozooplankton cause a netreductionin export production; a general introduction of zooplankton would therefore have reduced carbon burial and moderated the bloom and bust cycle that must have characterized Proterozoic populations of net phytoplankton. The effect of added trophic levels in Early Cambrian ecosystems can be viewed as a serial application of the trophic cascade process observed in modern lakes, whereby the introduction of higher trophic levels determines the accumulation of plant biomass at the base of the system. As such, the major biogeochemical perturbations that mark the onset of the Phanerozoic might be considered a consequence, rather than a cause, of the Cambrian explosion; reduced C export due to zooplankton expansion explains the otherwise anomalous drop in δ13C at the base of the Tommotian.

Cambrian acanthomorphic acritarchs likely derived from planktic leiosphaerids exposed to mesozooplanktic grazing pressure, the ornamentation effectively increasing vesicle size without compromising buoyancy or surface-area:volume ratios. Alternatively, they may represent an escape into the plankton through a miniaturization of the much larger Neoproterozoic acanthomorphs. An invasion of small benthic herbivores into the water column to exploit the phytoplankton accounts for the origin of the mesozooplankton and may have been the key innovation in the Cambrian explosion.
Community paleoecology as an epiphenomenal science
Authors: Hoffman Antoni
Published: July 2016

The most important topics discussed thus far by community paleoecologists are: community approach to paleoenvironmental reconstruction, community development in evolutionary time, and community constraints upon species evolution. The first step in community-paleoecological analysis is to reconstruct the paleocommunity or paleoecosystem. However there are severe methodological limitations to any inference drawn from the composition and structure of a fossil assemblage. These result from various taphonomic biases. These constraints upon reliability of a community-paleoecological analysis are the least severe in the case of Cenozoic (and possibly Cretaceous) tropical to subtropical, molluskdominated, subtidal, benthic communities.

The basic assumption of community paleoecology is that communities or biocoenoses represent a distinct, real level of biotic organization achieved through ecological integration of and coevolution among the species. This assumption seems to be invalid for two reasons. (1) The actual degree of community integration is in general insufficient to induce any driving forces for a structural development as predicted by the system theory. (2) The concept of biological reality and distinctness of the community level of biotic organization implies assignment of a significant role to group selection. The assumption that ecological communities achieve with time an equilibrium state representing an optimum habitat partitioning among the component species is invalid, at least as a generalization. This idea is largely falsified and refuted by a variety of ecological studies. Ecological communities are then merely an epiphenomenon of the overlap in distributional patterns of various organisms. There is no intrinsic, biotic mechanism inducing community dynamics in either ecological, or evolutionary time.

In spite of this conclusion, the so-called “community approach” under favorable taphonomic conditions is among the most reliable methods of paleoenvironmental reconstruction, and the data on so-called “community evolution” are relevant to the problem of a relationship between actually realized niche patterns and their environmental framework. The latter problem can also be approached through analysis of longevity-frequency-distributions of chronospecies found living together in various habitats. A preliminary investigation may indicate that the precondition to optimization of niche dimensions through coevolution among ecologically related species was met in subtidal benthic habitats but not in pelagic ones. To account for a niche subdivision among planktonic organisms, one has therefore to invoke a stochastic pattern of speciation rather than coevolutionary mechanisms.
Functional morphology of Cretaceous helically-coiled ammonite shells
Authors: Ward Peter
Published: July 2016

Torticonic (helically-coiled) ammonoids have been most commonly interpreted as vagile, benthonic forms. Their mode of coiling, however, places the siphuncle in a functionally dorsolateral, rather than ventral position on the shell whorl due to: 1) their probable apex-upward shell orientation during life, and 2) size asymmetry of the lateral sutural saddles due to helical coiling, associated with upward siphuncle displacement. The resultant positioning of the siphuncle produces cameral liquid de-coupling soon after initiation of cameral liquid removal (emptying of liquid from a newly formed chamber within the phragmocone). Since in Recent chambered cephalopods cameral liquid de-coupling increases efficiency of vertical migration, a similar mode of life was indicated for the torticonic ammonites.
On fossil preservation and the stratigraphic ranges of taxa
Authors: Solow Andrew R. , Smith Woollcott
Published: July 2016

The fossil record is incomplete in the sense that taxa for which there are no preserved finds are unrepresented. Because the probability that there is at least one preserved find is greater for long-lived taxa, failure to account for this effect will bias estimation of mean taxonomic duration. This paper describes maximum likelihood estimation of mean taxonomic duration, fossil preservation rate, and completeness of the local fossil record under a model in which duration has an exponential distribution and the locations of preserved finds follow a Poisson process. The estimates under this model have simple closed forms. It is also straightforward to construct confidence regions for the model parameters. The method is applied to data on 110 trilobite species from the Upper Cambrian—Lower Ordovician in Oklahoma.
Did lungs and the intracardiac shunt evolve to oxygenate the heart in vertebrates?
Authors: Farmer Colleen
Published: July 2016

Traditional wisdom of the evolution of lungs in fishes is that lungs arose when gill ventilation was hindered by an aquatic habitat that was low in oxygen. This scenario has been buttressed primarily by a proposed correlation between extant air-breathing fishes and hypoxic habitats, as well as by the fact that early vertebrate fossils were found in sediments believed to indicate a semi-arid environment. There are problems with this scenario, yet it retains a dominant influence on how the evolution of aerial respiration is viewed. This paper presents a new hypothesis for lung evolution that is more consistent with the fossil record and physiology of extant animals than the traditional scenario; I propose that lungs evolved to supply the heart with oxygen. The primitive vertebrate heart was spongy in architecture and devoid of coronary support, obtaining oxygen from luminal blood. By supplying oxygen to this tissue, lungs may have been important in ancient fishes for sustaining activity, regardless of environment. Furthermore, this function for lungs may have influenced cardiovascular adaptations of tetrapods because their divided cardiovascular system isolates the right side of the heart from pulmonary oxygen. I propose that three innovations compensate for this isolation: In extant amphibians oxygen-rich blood from cutaneous and buccal respiration enters the right side of the heart; in chelonians and lepidosaurs the intracardiac shunt washes oxygen-rich blood into the right side of the heart; in mammals, birds, and perhaps in crocodilians, support of the heart by coronary vasculature eliminates this problem.
Supersonic sauropods? Tail dynamics in the diplodocids
Authors: Myhrvold Nathan P. , Currie Philip J.
Published: July 2016

Computer models of the tail ofApatosaurus louisaeshow it could reach supersonic velocities, producing a noise analogous to the “crack” of a bullwhip. Similarity in tail structure suggests this was feasible for other diplodocids, and possibly for unrelated sauropods likeMamenchisaurusand the dicraeosaurids. Lengthening of caudal vertebrae centra between positions 18 and 25 is consistent with adaptation to the stresses generated by such tail motion, as is coossification of vertebrae via diffuse idiopathic skeletal hyperostosis (DISH), which occurs in the same region in about half the specimens. The noise produced may have been used for defense, communication, intraspecific rivalry, or courtship, in which case supersonic “cracking” may have been a sexually dimorphic feature. Comparisons with the club-bearing tails of the sauropodsShunosaurus liiandOmeisaurus tianfuensisshow the diplodocid whiplash tail was not well adapted as a direct-impact weapon, bringing the tail-as-weapon hypothesis into doubt.
Patterns of turnover in Middle and Upper Ordovician brachiopods of the eastern United States: a test of coordinated stasis
Authors: Patzkowsky Mark E. , Holland Steven M.
Published: July 2016

A compilation of species occurrences in a chronostratigraphic framework of depositional sequences from a 250,000 km2area in the eastern United States is used to test for coordinated stasis in Middle and Upper Ordovician articulate brachiopods. Two rapid pulses of turnover in brachiopod species separate three periods of relatively lower turnover (ecologic-evolutionary [EE] subunits) that range from 3 to 9 m.y. in duration. Turnover within these EE subunits is characterized by high levels of percent species origination (ca. 60%) and percent species extinction (ca. 80%) and low levels of percent species persistence (<10%), all of which fall outside the range reported for coordinated stasis. Turnover between EE subunits is characterized by low levels of percent species holdover and percent species carryover (ca. 10% or less) and is consistent with coordinated stasis, although turnover pulses are driven largely by pulses in either extinction or origination, and not by pulses in both, as reported for coordinated stasis. Taken together, although these data display a marked bimodality in turnover, high levels of turnover within EE subunits is inconsistent with a pattern of coordinated stasis. Turnover rates within these EE subunits are much higher than previous global estimates for Cambro-Ordovician brachiopods or Phanerozoic marine species and indicate that local extirpation and migration play a significant role in regional biodiversity dynamics. Despite the high level of turnover observed within these EE subunits, some level of ecologic stability occurs because abundant genera persist throughout entire EE subunits. Ordovician species in this study behaved relatively independently of other taxa and were not tightly integrated as suggested by the broadly overlapping taxon abundance curves, the shifting habitat preference of some taxa, the piecemeal turnover between EE subunits, and the continuous creation of new species associations due to background levels of turnover within EE subunits. Turnover within EE subunits was associated with relatively stable or only mildly fluctuating environments. Rapid turnover between EE subunits was caused by extreme perturbations to the regional or possibly global ocean-climate system.
Phenetic discrimination of biometric simpletons: paleobiological implications of morphospecies in the lingulide brachiopodGlottidia
Authors: Kowalewski Michał , Dyreson Eric , Marcot Jonathan D. , Vargas José A. , Flessa Karl W. , Hallman Diana P.
Published: July 2016

The extreme morphological simplicity of lingulide brachiopod shells makes them particularly useful for investigating the species-level taxonomic resolution of the fossil record as well as the relationships between taxonomy, morphological complexity, and evolutionary rates. Lingulides have undergone little change in shell morphology and have had low taxonomic diversity since the Paleozoic. Is this pattern an evolutionary phenomenon or an artifact of the shell's simplicity? Multivariate methods were used to establish morphogroups among seven populations of four extant species ofGlottidia.Six characters (three shell dimensions and three internal septa) were measured for 162 specimens from field and museum collections. All populations follow similar allometric trajectories: internal septa display positive allometry and shell dimensions display negative allometry. The allometric pattern may reflect D'Arcy Thompson's Principle of Similitude. Principal component analysis does not reveal any distinct clusters inGlottidiamorphospace but suggests that some differences independent from ontogeny exist among the populations. Size-free canonical variate analysis indicates the presence of five size-invariant groups that are statistically distinct. Bootstrap-corrected error rates indicate that four specimens are enough to classify a sample correctly atα= 0.05 and eight specimens atα= 0.01. The groups are consistent with neontological classification with the exception of two populations ofG. pyramidataidentified by discriminant analysis as two distinct groups. The size-free morphogroups reflect geographic separation rather than ontogenetic or substrate differences among the populations.

Despite the morphological simplicity of the shell, size-free multivariate analysis ofGlottidiadelineates groups that offer taxonomic resolution comparable with the neontological classification. The method offers a promising tool for identifying natural morphogroups on the basis of few morphological characters. Moreover, the agreement between neontological taxonomy and the morphogroups suggests that the size-free approach can be applicable for evaluating the reality of the low diversity and turnover rates observed in the fossil record of lingulide brachiopods (= Family Lingulidae). Assuming that the neontological species ofGlottidiaare biologically meaningful, this study shows that morphological simplicity of lingulides does not necessarily result in taxonomic underresolution. Our analysis, as well as several previous case studies, suggests that taxonomic diversity and turnover rates do not have to be dependent on the morphological complexity of preservable parts. In many cases, when rigorous quantitative methods are employed, the differences in the rates of morphological evolution may be a real evolutionary phenomenon and not artifacts of morphological complexity.
Synchronized evolution in lineages of land snails in oceanic islands
Authors: Chiba Satoshi
Published: July 2016

Synchronous episodes of phenotypic change in five lineages of the endemic land snail genus Mandarina of the oceanic Bonin (Ogasawara) Islands through 40,000 years were documented by morphological analyses of radiocarbon-dated fossil specimens. Adult shell traits of these lineages show mostly synchronous patterns of change with longer intervals of stability and rapid shifts to other states of stability. Although there are intermediates between these different phenotypic states, the net interval of the phenotypic shift was relatively short, i.e., no longer than 7000 years. Extinction of a lineage and speciation occurred during the intervals of the rapid phenotypic shift. This period of abrupt change corresponds to the period of lowest sea level and end of the last glacial period. This implies that climatic change is one of the causes of these episodes of simultaneous rapid phenotypic shifts, speciation, and extinction in different lineages. These findings suggest that major phenotypic changes in phyletic evolution, separation of different species, and extinction of lineages may occur synchronously in many lineages during an extremely short interval.
A serious matter with character-taxon matrices
Authors: Vermeij Geerat J.
Published: July 2016

Knowing the structure and branching order of the evolutionary tree is essential to many studies of the evolutionary process and the history of life. Most attempts to reconstruct evolutionary trees are based on rectangular matrices, in which coded states are assigned for each character and each taxon under study. Everyone who has tried to infer the pattern of evolution from such character-taxon matrices is confronted with a great deal of “noise” and uncertainty. Often, there are multiple “most parsimonious trees” (those requiring the fewest evolutionary steps), which often differ significantly in topology; and many nodes in such trees are poorly supported; that is, there are contradictions and inconsistencies in the data. Some of this noise arises for reasons well known to phylogeneticists. Character states may arise multiple times, evolve in parallel, or reverse (homoplasy); taxa vary insufficiently among themselves; and diversification may be so rapid that data are insufficient to detect the order of branching. Polytomies are regarded as a nuisance rather than as real information. Characters may be coded inappropriately, so that there are too many redundancies, inapplicable character states, and multistate characters, as well as dependence among characters. Moreover, it is highly debatable whether evolution is parsimonious, and there are conflicts about how to establish the polarity of characters (primitive vs. derived). (For reviews and discussion see Sober 1988; Huelsenbeck and Crandall 1997.)
Decline in extinction rates and scale invariance in the fossil record
Authors: Newman M. E. J. , Eble Gunther J.
Published: July 2016

We show that the decline in the extinction rate during the Phanerozoic can be accurately described by a logarithmic fit to the cumulative total extinction. This implies that extinction intensity is falling off approximately as the reciprocal of time. We demonstrate that this observation alone is sufficient to explain the existence of the proposed power-law forms in the distribution of the sizes of extinction events and in the power spectrum of Phanerozoic extinction, results that previously have been explained by appealing to self-organized critical theories of evolutionary dynamics.
Biogeographic analyses of the Ediacara biota: a conflict with paleotectonic reconstructions
Authors: Waggoner Ben
Published: July 2016

Paleotectonic reconstructions for the late Proterozoic have differed over the timing of the Cordilleran rifting between Laurentia and the East Gondwana cratons. Parsimony Analysis of Endemism (PAE) and phenetic clustering of the “Ediacara biota” were carried out, for comparison with competing paleotectonic hypotheses. All analyses show a common pattern of similarities among biotas. The biotas of Charnwood Forest and Newfoundland consistently group together, while the south Australian biota is closest to those of Baltica, northern Laurentia, and Siberia. The biota of southwest North America, though still poorly known, strikingly resembles that of Namibia—not that of northwestern Canada. This pattern is not obviously due to facies-related or preservational bias and is very different from Cambrian biogeographic patterns. The overall pattern is most consistent with the hypothesis that the western margin of Laurentia was in close contact with East Gondwana, with rifting taking place either during or just before the Vendian. This arrangement has been previously proposed as a paleotectonic hypothesis; however, most recent paleomagnetic and structural studies support the alternate hypothesis that this rifting took place more than 100 million years before the Vendian. Resolving this contradiction will require much more data on both organismal distribution and cratonal position.
Paleontological paradigms and inferences of phylogenetic pattern: a case study
Authors: O'Keefe F. Robin , Sander P. Martin
Published: July 2016

In this paper we reconstruct the phylogeny of a clade of pachypleurosaurs (Reptilia: Sauropterygia) occurring in Triassic-age deposits in the Monte San Giorgio region, Switzerland. We also present the phylogeny of this clade as a case study for two paradigms of phylogeny reconstruction: cladistics and phenetic/stratigraphic methods. While this dichotomy is not held rigidly by all workers, its advancement by cladists leads us to retain it initially for rhetorical purposes. We review the philosophical bases of species, species concepts, and speciation, as well as cladograms and phylogenies, before introducing the experimental system.

Data are presented from cladistic analyses, phenetic analyses, and stratigraphic information. Phylogeny of the clade is interpreted from both paradigms, and the interpretations are found to be inconsistent. Resolution of the phylogeny rests on the emphasis of one type of data over another. An interpretation of cladogenesis within the genusNeusticosaurusentails rejection of suggestive phenetic and stratigraphic data, whereas an anagenetic interpretation entails reversal of autapomorphies in ancestral taxa. Anagenesis is deemed to be the more probable interpretation, based on the strength of the stratigraphic and phenetic data relative to the character data. Implications of the test case results for phylogeny reconstruction in general are discussed, ending with a call for pluralism in approach.
The time of origin of whales and the role of behavioral changes in the terrestrial-aquatic transition
Authors: O'Leary Maureen A. , Uhen Mark D.
Published: July 2016

Addition of the recently discovered fossil Nalacetus to a phylogenetic analysis of basicranial, cranial, dental, postcranial, and soft morphological characters reveals that it is the most basal cetacean, and that mesonychians form the monophyletic sister group to Cetacea. The molars of Nalacetus elucidate transformations in dental morphology that occurred early in the cetacean radiation and clarify certain derived differences in molar cusp position between cetaceans and the extinct clade, Mesonychia, hypothesized to be their sister taxon. Nalacetus and other archaic cetaceans share derived vertically elongate shearing facets on the lower molars. Applying the Extant Phylogenetic Bracket, we advance the hypothesis that these facets are an osteological correlate of aquatic predation. Our functional interpretation of this character and its distribution within Cetacea indicates that a behavioral change in tooth use characterized the origin of the clade. Comparison of the transformation of this dental character with that of the cetacean pelvis indicates that a change in tooth use (feeding behavior) occurred before loss of the ability to engage in terrestrial locomotion.

The most parsimonious phylogenetic hypothesis presented here has a significant fit with the stratigraphic record as determined by the Manhattan Stratigraphic Measure, which is corroborated by retention indices of stratigraphic data. Ghost lineages necessitated by the phylogenetic hypothesis extend the stratigraphic range of Cetacea into the middle Paleocene (Torrejonian), ten million years earlier than the oldest cetacean fossil currently known. Primitive features of Nalacetus, the large number of synapomorphies diagnosing Cetacea, and the implied ghost lineage suggest that the early cetacean radiation was much more extensive than has been previously recognized.
Comparing palynological abundance and diversity: implications for biotic replacement during the Cretaceous angiosperm radiation
Authors: Lupia Richard , Lidgard Scott , Crane Peter R.
Published: July 2016

The Cretaceous radiation of angiosperms initiated a major reorganization of terrestrial plant communities as dominance by pteridophytic and gymnospermic groups eventually gave way to dominance by angiosperms. Previously, patterns of biotic replacement have been assessed using measures based on taxonomic diversity data. However, using measures of both abundance and diversity to investigate replacement patterns provides more information about macroecological change in the fossil record than either can provide alone. Analyses of an updated and expanded database of North American palynological samples from Cretaceous sediments document a rapid increase in angiosperm diversity and abundance within individual fossil palynofloras (representing local/subregional vegetation). New analyses of floristic diversity patterns support previous results and indicate that the decline of free-sporing plants is more pronounced than the decline of gymnosperms. In contrast, analyses of abundance data appear to show that the decline of gymnosperms is far more pronounced than the decline of free-sporing plants. Detailed examination of both data sets segregated by paleolatitude shows that this apparent contradiction reflects biogeographical differences in the patterns of vegetational change (e.g., free-sporing plants declined in abundance at lower latitudes) as well as sampling bias (e.g., greater sampling in the northern region in the Late Cretaceous). Analyses accounting for these biases support the conclusion that as angiosperms radiated, free-sporing plants rather than gymnosperms (in this case, mainly conifers) experienced the most pronounced decline. A thorough understanding of the Cretaceous radiation of angiosperms will require both abundance and diversity data. It also will require expanding the analyses presented here into other geographic regions as well as sampling more completely at all spatial scales.
Morphological evolution of the murine rodent Paraethomys in response to climatic variations (Mio-Pleistocene of North Africa)
Authors: Renaud Sabrina , Benammi Mouloud , Jaeger Jean-Jacques
Published: July 2016

The North African murine rodent Paraethomys evolved as an anagenetic lineage from the late Miocene until its extinction in the late—middle Pleistocene. A Fourier analysis of the outlines of the first upper and lower molars of this rodent was used to quantify the evolutionary patterns of this lineage and to compare evolutionary patterns to the climatic record. Morphological evolution and long-term environmental variations are strongly correlated. A change in molar shape, which may be related to the development of a more grass-eating diet, corresponds to the global cooling beginning around 3 Ma and the subsequent increase in aridity in North Africa. Concurrently, size increased, which may be related to increased masticatory efficiency or to metabolic adaptation to the cooler environmental conditions according to Bergmann's rule. This adaptive response to changing environmental conditions corresponds to an acceleration of evolutionary rates in the lineage. The modalities of the evolutionary response in size and shape are probably controlled by intrinsic factors such as different genetic determinisms for both characters.
Strange Old World - Late Paleocene—Early Eocene Climatic and Biotic Events in the Marine and Terrestrial Record. Edited by Marie-Pierre Aubry, Spencer Lucas, and William Berggren Columbia University Press, New York. 1998. 513 pages.
Authors: Clyde William C.
Published: July 2016

In his 1932 book Brave New World, Aldous Huxley laid out a satirical blueprint of a future so strange to people of the time that it became a symbol of the frightening and unyielding momentum of scientific progress. Literature and popular culture have since been littered with images of a future earth so transformed by human progress (or extraterrestrial intervention) that we can hardly recognize it. Earth historians and paleontologists, however, have taken a different path into the bizarre. This group of time travelers has used the kind of technology that Huxley foreshadowed to recreate past worlds of similar disparity. These worlds are neither based on, nor entirely limited by, human imagination, but are based instead on scientific observation. In short, these strange old worlds are real, not imagined. As often is the case, however, truth can b e stranger than fiction.
Variation, sexual dimorphism, and social structure in the early Eocene horse Hyracotherium (Mammalia, Perissodactyla)
Authors: Gingerich Philip D.
Published: July 2016

Patterns of dental and cranial variation are analyzed in a unique sample of early Eocene equid Hyracotherium from one fossil quarry of late Wasatchian age in the Huerfano Basin of southern Colorado. The sample includes remains of two species differing principally in size: H. vasacciense and H. tapirinum. The larger species, H. tapirinum, is represented by 24 individual specimens that show marked bimodality in cranial size and robustness and in upper and lower canine size. These differences are attributed to sexual dimorphism. Males tend to be about 15% larger than females in cranial dimensions and 40% larger than females in canine dimensions suggesting, by comparison with modern ungulates, that early Eocene horses were probably polygynous. The appearance of Hyracotherium in North America and its rise to dominance in early Eocene mammalian communities coincides with development of an environmental mosaic including open park woodland and savanna habitats. The evolutionary success of Hyracotherium may reflect, in part, the adaptive superiority of a social structure in which females in open habitats are grouped for mutual protection from predators, for optimal foraging in patchy environments, or both.
Post-mortem ascent of Nautilus shells: implications for cephalopod paleobiogeography
Authors: Chamberlain John A. , Ward Peter D. , Weaver J. Scott
Published: July 2016

Analysis of post-mortem buoyancy loss in Nautilus shells suggests that extensive nekroplanktonic drifting occurs infrequently. Most shells do not reach the surface but settle to the sea floor, after a short period of ascent. This occurs because the rate of water influx into the phragmocone due to ambient hydrostatic pressure is sufficiently rapid in most cases to overcome positive buoyancy before the shell reaches the surface. The resulting geographic distribution of Nautilus shells would therefore mirror the distribution of the live animals. Thus, post-mortem drift in Nautilus cannot be used as a basis for questioning the validity of cephalopod paleobiogeography. Estimate of influx rates in ammonoid siphuncles indicates that many, if not most, ammonoid shells also would not become nekroplanktonic. This is especially true for small (<5 cm diameter) shells. Cephalopod paleobiogeographic investigation appears less subject to criticism stemming from the supposed obfuscating effects of post-mortem drift than previously thought.
Competition wins out overall: Reply to Paine
Authors: Newman William A. , Stanley Steven M.
Published: July 2016

A number of facts indicate that the diversity of chthamaloid barnacles is much lower now than it has been in the past. Among these are the relict, often disjunct geographic distributions of distinctive chthamaloid higher taxa and their representation by only a few living species. The living chthamaloid barnacles also have a disjunct bathymetric distribution: as we will document here in detail, they are concentrated in the intertidal zone and in deep water. In his rejoinder to our paper, Paine makes no cogent argument against our interpretations of this powerful evidence.

Our case that the balanoids have competitively displaced the more primitive chthamaloids is based on several facts: (1) the Chthamaloidea have dwindled during the Cenozoic Era, so that most have relict or refugial distributions, whereas the Balanoidea have undergone a remarkable adaptive radiation; (2) balanoid species are known to defeat chthamaloid species in competition for space; (3) the competitive success of the balanoids can be attributed to an inherent biological feature—a tubiferous skeleton, which fosters rapid growth; (4) the peak diversity of living balanoids coincides precisely with the bathymetric gap in the chthamaloids’ distribution.

We argue that the radiation of balanoids during the past 40 Myr or so has caused a decline in chthamaloid diversity by reducing and destabilizing low intertidal and shallow subtidal populations, thus elevating average rate of extinction and depressing average rate of speciation. This model allows for exceptions to the rule of balanoid competitive dominance, but contrary to Paine's claim, the exceptions that exist are either trivial or support our view.

Paine offers no alternative to our competition hypothesis. He suggests that an increase in predation has caused a decline in chthamaloid body size, but neither a Cenozoic trend in body size nor one in predation pressure has empirical support; furthermore, the body-size hypothesis has no direct bearing on the case we have presented.
Origination preceding extinction during late Cenozoic turnover of Caribbean reefs
Authors: Budd Ann F. , Johnson Kenneth G.
Published: July 2016

Statistical analyses of occurrence data derived from new collections through scattered Caribbean sections indicate that increased speciation preceded a pulse of extinction during regional turnover of the Caribbean reef coral fauna in Plio-Pleistocene time. The data are based on samples that were newly collected and identified to species using standardized procedures. Age-dates were assigned using high-resolution chronostratigraphic methods. The results show that coral species with a wide range of ecological traits originated and were added to the species pool as much as 1–2 million years before extinction peaked at the end of the turnover interval. Local assemblages consisted of a mix of extinct and living species, which varied in composition but not in richness. Extinction was selective and resulted in a faunal shift to the large, fast-growing species that dominate Caribbean reefs today. The unusual relationship between origination and extinction may have been caused by changes in oceanic circulation associated with emergence of the Central American Isthmus, followed by the onset of Northern Hemisphere glaciation. The pattern of origination preceding extinction may have been responsible for the stability of reef ecosystems during the intense climatic fluctuations of the late Pleistocene, and for the composition and structure of modern Caribbean reef ecosystems.
I. Observations on the History of St. George, the Patron Saint of England; wherein Dr. Pettingal's allegorical Interpretation of the Equestrian Figure on the George; and the late Mr. Byrom's Conjecture, that St. George is mistaken for Pope Gregory are briefly confuted. And the Martyr of Cappadocia, as Patron of England, and of the Order of the Garter, is defended against both
Authors: Pegge Samuel
Published: July 2016

The connection of the Society of Antiquaries with the Patron of the English Nation St. George, whose Anniversary is the day appointed by statute for the Election of their Officers, and whereof the King's most excellent Majesty is the Founder and Patron, as well as Sovereign of the Order of St. George, seems to make it necessary that some proper notice should be taken, by some of its members, of two late publications tending to the Annihilation of this Saint. There can be no reason, at this day, against an Enquiry into the truth of the Admission and Acceptance of St. George, the Martyr, by our Ancestors as the Patron and Protector of this kingdom; especially since Dr. Pettingal, Author of one of the Pieces alluded to, supposes the George and Garter to be entirely of an emblematical or allegorical Nature; and Mr. Byrom, Author of the other Piece, has declared, that St. Gregory the Great, Bishop of Rome, and not St. George, was the real Patron-Saint of the English.
III. Mr. Barrington on some additional Information relative to the Continuance of the Cornish Language. In a Letter to John Lloyd, Esq. F.A.S.
Authors: Barrington
Published: July 2016

I some time since addressed to you several particulars relative to the remains of the Cornish language, which the Society of Antiquaries did me the honour to insert in the Third Volume of the Archaeologia (p. 278). It may not be improper therefore to lay before the Society some further information on this head, which the Rev. Mr. Penneck, F. R. S. hath been so obliging as to procure for me.
XVI. Thomas Morell Honoratissimo Viro Daines Barrington
Authors: Morell Thomas
Published: July 2016

Me dudum tibi, vir eruditissime, illam etiam alteram Corbrigiensem inscriptionem excutere, et cogitationes meas rescribere (mutuo conferendi gratia, non edendi) pollicitum suisse, haud diffiteor. Sed et otium et materies mihi defuêrunt. Si enim in hac inscriptione aliquid obscuri, aut difficile intellectu inesset, quid tuam diligentiam, quid tuam in antiquitatis monumentis eruditionem potuit fugere? Quin et Jacobus Oberlinus, in orbis antiqui monumentis suis illustrati Prodromo, rectè admonet, quàm cautè sit in dijudicandis interpretandisque monumentis versandum. Cum verò nomina negligentiae me suspectum esse nollem, en tibi pauca, non ad aliquid novi proserendum, sed ad tuam sententiam, sicut prius, confirmandam, commentata.
XXXVI. The Question discussed concerning the Appearance of the Matrices of so many Conventual Seals. By Mr. Pegge. In a Letter to Gustavus Brander, Esquire
Authors: Pegge
Published: July 2016

There are an infinite variety of seals engraved in authors, and amongst them a confiderable number of conventual ones. Most of these last have been taken from impressions in wax appendant to old deeds and charters, but others have been copied from the matrices themselves still remaining amongst us. You, Sir, have a most valuable collection of these latter, and other gentlemen of my acquaintance are possessed of many, insomuch that all together they amount to a considerable number.
XL. Some further Remarks on the Origin of the English Language. By the Rev. Mr. Drake. In a Letter to the Secretary
Authors: Drake
Published: July 2016

You may recollect, that some time ago I had the honour of communicating to the Society, a paper, asserting the Teutonic original of the English language, contrary to the opinion of a celebrated writer of antiquity, who chiefly confines it to a Celtic one. You may remember also, that in order to confirm my position, I confronted a portion of the Gothic version of the gospel, as it appears in the Codex Argenteus, with our common translation of the same chapter, and I believe you was surprized to observe how striking a resemblance the English tongue had with the Gothic. It may perhaps be some entertainment if I should pursue the subject; for which purpose I shall again place together another part of the two different versions, and compare them in the same manner I did before, that by an actual collation of the two languages, a Gothic original of the English tongue may demonstrably appear. For this design I shall select a few circumstances relative to the crucifixion of our Saviour, as described by St. Mark, and without further introduction lay them before you.
I. Observations on the Julia Strata, and on the Roman Stations, Forts, and Camps, in the Counties of Monmouth, Brecknock, Caermarthen, and Glamorgan. By the Rev. William Harris, Prebendary of Landaff, and Curate of Caireu
Authors: Harris William
Published: July 2016

It is probable that Julius Frontinus, Prefect of the Legio 2da Augusta under Vespasian, who was detached to reduce the Silures, and from whom Julia Strata is said to have been denominated, passed the Severn three little miles below Oldbury, at Awst passage, perhaps termed from that legion, Trajectus Augustæ; as the Monk of Ravenna stiles Caerleon Isca Augusta, and the Britons at this day call the month of August Mîs Awst.
III. An Account of some Antiquities found in Ireland; communicated by the Right Reverend Richard Pococke, late Lord Bishop of Meath
Authors: Pococke Richard
Published: July 2016

In March, 1748, while some ploughmen were tilling lands upon Carne, the estate of Keedah Geoghagen, esq; about seven miles west of Mullingar, in the county of Westmeath, the plough, cutting through a sandy hillock which lay in the middle of the field, turned up a flag stone, about four feet long and three broad. Underneath they discovered a grave, or rather ossuary, to which this stone had served as a cover. The bottom, sides, and ends of the grave were composed each of a single slab. Within were deposited the bones of a human body, but of a size greatly above the common proportion of men.
V. An Account of a remarkable Monument, in Penrith Church Yard, Cumberland. By Dr. Lyttelton, then Dean of Exeter
Authors: Lyttelton
Published: July 2016

In a tour I made the last summer, over part of the north of England, I met with a remarkable Monument in Penrith Church-yard, in Cumberland, an elevation of which I now do myself the pleasure of laying before you, it having never been yet engraved, or, indeed, accurately described by any author. It is called the Giants Grave; and we have the following account of it in Bishop Gibson's edition of the Britannia (Vol. II. p. 1020) communicated to him (as I was informed) by Dr. Todd, of Carlisle.
XXXI. Some Remarks on Mr. Walpole's Historic Doubts on the Life and Reign of King Richard the Third, by Robert Masters, B. D. and Rector of Landbeach, in Cambridgeshire
Authors: Masters Robert
Published: July 2016

When Mr. Walpole's Historic Doubts were first published, I sat down with great eagerness to peruse what could be offered by an author of his acutenese upon so interesting an article in our English History. After examining the authors referred to as I went along, I made the following remarks, more for my own satisfactction, than with design of communicating them to the public; but as Dean Milles's ingenious Observations on the same subject have been read before the Society, and deservedly obtained a place amongst their Miscellaneous Tracts lately published, I take the liberty of laying these before them, with great deference to their judgement, as a supplement thereto, he having chosen to confine himself chiefly to the Wardrobe Account, which he has handled in so masterly a manner, as, in my opinion, intirely to overset all the arguments built upon it.
XXXV. A Description of the Sepulchral Monument at New Grange, near Drogheda, in the County of Meath, in Ireland. By Thomas Pownall, Esq; in a Letter to the Rev. Gregory Sharpe, D.D. Master of The Temple
Authors: Pownall Thomas
Published: July 2016

The sole object I had in view when I first sat down to write, I was to give you an account of a very singular and curious monument of antiquity at New Grange, in the county of Meath, in Ireland; and I meant to have confined this account to a mere description of particulars. But when I came to consider these particulars under reference to the general customs of times more remote than the highest antiquity this monument can be supposed to boast; that consideration opened a field for disquisitions of a much more general and extensive scope.
XXXVI. Account of a Roman Pavement, with Wheat underneath it, found at Colchester. By the Rev. Dr. Griffith; communicated by Edward King, Esq; in a Letter to the Secretary
Authors: Griffith
Published: July 2016

Having received, from the Reverend Dr. Griffith, Rector of St. Mary Hill, the inclosed account of a curious discovery lately made at Colchester, I take the liberty to trouble you with it; that, is you esteem it at all worthy the attention of the Society, you may communicate it to them. I will only just take the liberty to add, that, in pulling down the old tower of the church at Mold, in North Wales, last year, a great quantity of grain was found buried under its foundations, in like manner; and that probably it was deposited in both places, in consequence of some ancient superstitious custom.
XLII. Extract of a Letter from the Reverend Mr. Bentham, of Ely, to the Dean of Exeter, concerning certain Discoveries in Ely Minster
Authors: Bentham
Published: July 2016

Give me leave to add the following particulars (by way of additional note to what is said in the History and Antiquities of the Church of Ely, page 85,) concerning the removal of some Bones, in the pious conservation of which our ancestors were pleased to interest themselves, from a grateful remembrance of that beneficence which the persons there mentioned had exercised towards the Religious of this place. These bones had for a long time been immured within the north wall of the late choir. When it became necessary, on account of removing the choir to the east end of the church, to take down that wall, I thought proper to attend; and also gave notice of it to several gentlemen, who were desirous of beng present when the wall was demolished. There were the traces of their several effigies on the wall, and over each of them an inscription of their names. Whether their relicks were still to be found was uncertain; but I apprised those who attended on that occasion, May 18, 1769, that, if my surmises were well founded, no head would be found in the cell which contained the bones of Brithnoth, duke of Northumberland.
I. Of the Horn, as a Charter or Instrument of Conveyance. Some Observations on Mr. Samuel Foxlowe's Horn; as likewise on the Nature and Kinds of these Horns in general. By Mr. Pegge
Authors: Pegge
Published: July 2016

Amongst the various methods of transferring inheritances in use with our ancestors was that of conveying them by a Horn, either in Frank Almoigne, or in Fee, or in Serjeantry. Ingulphus, abbot of Croyland, particularly specifies the Horn amongst those things whereby lands were conveyed in the beginning of the Conqueror's reign. His words are too remarkable to be omitted on this occasion; ‘Conferebantur etiam primo multa ‘praedia nudo verbo, absque scripto vel cbartâ, tantum cum dominī ‘gladio, vel gateâ, vel cornu, vel craterâ; et plurima tenementa cum ‘calcari, cum strigili, cum arcu; et nonnulla cum sagittâ. At first ‘(says he, speaking of the Conqueror's time) many estates were ‘transferred by bare word of mouth, without any writing or char ‘ter, only by the Lord's sword, or helmet, or born, or cup; and ‘many tenements by a spur, a scraper, a bow; and some by an ‘arrow.’ It should seem by this account given us by Ingulphus, which is to clear and express, that the implement was always such as was well known to have belonged to the donor or grantor.