scholarly journals Ecogeochemistry potential in deep time biodiversity illustrated using a modern deep-water case study

2016 ◽  
Vol 371 (1691) ◽  
pp. 20150223 ◽  
Author(s):  
Clive N. Trueman ◽  
Ming-Tsung Chung ◽  
Diana Shores

The fossil record provides the only direct evidence of temporal trends in biodiversity over evolutionary timescales. Studies of biodiversity using the fossil record are, however, largely limited to discussions of taxonomic and/or morphological diversity. Behavioural and physiological traits that are likely to be under strong selection are largely obscured from the body fossil record. Similar problems exist in modern ecosystems where animals are difficult to access. In this review, we illustrate some of the common conceptual and methodological ground shared between those studying behavioural ecology in deep time and in inaccessible modern ecosystems. We discuss emerging ecogeochemical methods used to explore population connectivity and genetic drift, life-history traits and field metabolic rate and discuss some of the additional problems associated with applying these methods in deep time.

2015 ◽  
Vol 282 (1810) ◽  
pp. 20150569 ◽  
Author(s):  
Michael J. Benton

Macroevolution, encompassing the deep-time patterns of the origins of modern biodiversity, has been discussed in many contexts. Non-Darwinian models such as macromutations have been proposed as a means of bridging seemingly large gaps in knowledge, or as a means to explain the origin of exquisitely adapted body plans. However, such gaps can be spanned by new fossil finds, and complex, integrated organisms can be shown to have evolved piecemeal. For example, the fossil record between dinosaurs and Archaeopteryx has now filled up with astonishing fossil intermediates that show how the unique plexus of avian adaptations emerged step by step over 60 Myr. New numerical approaches to morphometrics and phylogenetic comparative methods allow palaeontologists and biologists to work together on deep-time questions of evolution, to explore how diversity, morphology and function have changed through time. Patterns are more complex than sometimes expected, with frequent decoupling of species diversity and morphological diversity, pointing to the need for some new generalizations about the processes that lie behind such patterns.


2018 ◽  
Vol 5 (3) ◽  
pp. 171991 ◽  
Author(s):  
Sandra R. Schachat ◽  
Conrad C. Labandeira ◽  
S. Augusta Maccracken

Sampling standardization has not been fully addressed for the study of insect herbivory in the fossil record. The effects of sampling within a single locality were explored almost a decade ago, but the importance of sampling standardization for comparisons of herbivory across space and time has not yet been evaluated. Here, we present a case study from the Permian in which we evaluate the impact of sampling standardization on comparisons of insect herbivory from two localities that are similar in age and floral composition. Comparisons of insect damage type (DT) diversity change dramatically when the number of leaves examined is standardized by surface area. This finding suggests that surface area should always be taken into account for comparisons of DT diversity. In addition, the three most common metrics of herbivory—DT diversity, proportion of leaves herbivorized and proportion of leaf surface area herbivorized—are inherently decoupled from each other. The decoupling of the diversity and intensity of insect herbivory necessitates a reinterpretation of published data because they had been conflated in previous studies. Future studies should examine the divergent ecological factors that underlie these metrics. We conclude with suggestions to guide the sampling and analysis of herbivorized leaves in the fossil record.


2019 ◽  
Vol 9 (5) ◽  
pp. 158-160
Author(s):  
Sonali Harish Ghongade

The common cause of all diseases is the accumulation of waste and poisonous matter in the body. The ancient and modern science of healthcare management described various modalities for the treatment of different diseases and naturopathy is one of them. Naturopathy is a natural system that removes toxic matter and strengthens physiological functioning of body. Naturopathy treats diseases without medication and generally not deteriorates functioning of vital organs of the body. Natural therapies such as; application of cold water compression, mud application, sun bath, lifestyle management and diet etc. cure diseases by stimulating vitality of the body. Present article explored use of naturopathy in case of diabetes, article summarized effect of naturopathy in the management of diabetes using a clinical case study. Keywords: Naturopathy, Disease, Diabetes, Sun Bath, Lifestyle   


2015 ◽  
Vol 282 (1821) ◽  
pp. 20152023 ◽  
Author(s):  
Mark N. Puttick ◽  
Gavin H. Thomas

Most of life is extinct, so incorporating some fossil evidence into analyses of macroevolution is typically seen as necessary to understand the diversification of life and patterns of morphological evolution. Here we test the effects of inclusion of fossils in a study of the body size evolution of afrotherian mammals, a clade that includes the elephants, sea cows and elephant shrews. We find that the inclusion of fossil tips has little impact on analyses of body mass evolution; from a small ancestral size (approx. 100 g), there is a shift in rate and an increase in mass leading to the larger-bodied Paenungulata and Tubulidentata, regardless of whether fossils are included or excluded from analyses. For Afrotheria, the inclusion of fossils and morphological character data affect phylogenetic topology, but these differences have little impact upon patterns of body mass evolution and these body mass evolutionary patterns are consistent with the fossil record. The largest differences between our analyses result from the evolutionary model, not the addition of fossils. For some clades, extant-only analyses may be reliable to reconstruct body mass evolution, but the addition of fossils and careful model selection is likely to increase confidence and accuracy of reconstructed macroevolutionary patterns.


Paleobiology ◽  
2001 ◽  
Vol 27 (2) ◽  
pp. 405-423 ◽  
Author(s):  
Daniel. W. McShea

The degree of hierarchical structure of organisms—the number of levels of nesting of lower-level entities within higher-level individuals—has apparently increased a number of times in the history of life, notably in the origin of the eukaryotic cell from an association of prokaryotic cells, of multicellular organisms from clones of eukaryotic cells, and of integrated colonies from aggregates of multicellular individuals. Arranged in order of first occurrence, these three transitions suggest a trend, in particular a trend in the maximum, or an increase in the degree of hierarchical structure present in the hierarchically deepest organism on Earth. However, no rigorous documentation of such a trend—based on operational and consistent criteria for hierarchical levels—has been attempted. Also, the trajectory of increase has not been examined in any detail. One limitation is that no hierarchy scale has been developed with sufficient resolution to document more than these three major increases. Here, a higher-resolution scale is proposed in which hierarchical structure is decomposed into levels and sublevels, with levels reflecting number of layers of nestedness, and sublevels reflecting degree of individuation at the highest level. The scale is then used, together with the body-fossil record, to plot the trajectory of the maximum. Two alternative interpretations of the record are considered, and both reveal a long-term trend extending from the Archean through the early Phanerozoic. In one, the pattern of increase was incremental, with almost all sublevels arising precisely in order. The data also raise the possibility that waiting times for transitions between sublevels may have decreased with increasing hierarchical level (and with time). These last two findings—incremental increase in level and decreasing waiting times—are tentative, pending a study of possible biases in the fossil record.


2020 ◽  
Vol 117 (16) ◽  
pp. 8966-8972 ◽  
Author(s):  
Gregory D. Edgecombe ◽  
Christine Strullu-Derrien ◽  
Tomasz Góral ◽  
Alexander J. Hetherington ◽  
Christine Thompson ◽  
...  

Identifying marine or freshwater fossils that belong to the stem groups of the major terrestrial arthropod radiations is a longstanding challenge. Molecular dating and fossils of their pancrustacean sister group predict that myriapods originated in the Cambrian, much earlier than their oldest known fossils, but uncertainty about stem group Myriapoda confounds efforts to resolve the timing of the group’s terrestrialization. Among a small set of candidates for membership in the stem group of Myriapoda, the Cambrian to Triassic euthycarcinoids have repeatedly been singled out. The only known Devonian euthycarcinoid, Heterocrania rhyniensis from the Rhynie and Windyfield cherts hot spring complex in Scotland, reveals details of head structures that constrain the evolutionary position of euthycarcinoids. The head capsule houses an anterior cuticular tentorium, a feature uniquely shared by myriapods and hexapods. Confocal microscopy recovers myriapod-like characters of the preoral chamber, such as a prominent hypopharynx supported by tentorial bars and superlinguae between the mandibles and hypopharynx, reinforcing an alliance between euthycarcinoids and myriapods recovered in recent phylogenetic analysis. The Cambrian occurrence of the earliest euthycarcinoids supplies the oldest compelling evidence for an aquatic stem group for either Myriapoda or Hexapoda, previously a lacuna in the body fossil record of these otherwise terrestrial lineages until the Silurian and Devonian, respectively. The trace fossil record of euthycarcinoids in the Cambrian and Ordovician reveals amphibious locomotion in tidal environments and fills a gap between molecular estimates for myriapod origins in the Cambrian and a post-Ordovician crown group fossil record.


Rhizomata ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 239-267
Author(s):  
Kathryn Morgan

Abstract This paper uses a problematic passage at Phaedo 69a–c as a case study to explore the advantages we can gain by reading Plato in his cultural context. Socrates argues that the common conception of courage is strange: people fear death, but endure it because they are afraid of greater evils. They are thus brave through fear. He proposes that we should not exchange greater pleasures, pains, and fears for lesser, like coins, but that there is the only correct coin, for which we must exchange all these things: wisdom (phronēsis). Commentators have been puzzled by the precise nature of the exchange envisaged here, sometimes labelling the coinage metaphor as inept, sometimes describing this stretch of argument as “religious” and thus not to be taken seriously. The body of the paper looks at (1) the connection between money and somatic materialism, (2) the incommensurability in Plato of financial and ethical orders, (3) financial metaphors outside Plato that connect coinage with ethics, (4) intrinsic and use values in ancient coinage, and (5) Athenian laws on coinage, weights, and measures that reflect anxiety about debased coins in the fifth and early fourth centuries. It sees the Phaedo passage as the product of a sociopolitical climate which facilitated the consideration of coinage as an embodiment of a value system and which connected counterfeit or debased currency with debased ethical types. Athenians in the early fourth century were much concerned with issues of commensurability between different currencies and with problems of debasement and counterfeiting; understanding this makes Socrates’ use of coinage metaphors less puzzling. Both the metaphor of coinage and the other metaphors in this passage of the Phaedo (painting and initiation) engage with ideas of purity, genuineness, and deception. Taken as a group, these metaphors cover a large area of contemporary popular culture and are used to illustrate a disjunction between popular and philosophical ways of looking at value.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10356
Author(s):  
Viktor A. Baranov ◽  
Yinan Wang ◽  
Rok Gašparič ◽  
Sonja Wedmann ◽  
Joachim T. Haug

Stratiomyomorpha (soldier flies and allies) is an ingroup of Diptera, with a fossil record stretching back to the Early Cretaceous (the Barremian, about 125 MYA). Stratiomyomorpha includes at least 3,000 species in the modern fauna, with many species being crucial for ecosystem functions, especially as saprophages. Larvae of many stratiomyomorphans are especially important as scavengers and saproxyls in modern ecosystems. Yet, fossil larvae of the group are extremely scarce. Here we present 23 new records of fossil stratiomyomorphan larvae, representing six discrete morphotypes. Specimens originate from Cretaceous amber from Myanmar, Eocene Baltic amber, Miocene Dominican amber, and compression fossils from the Eocene of Messel (Germany) and the Miocene of Slovenia. We discuss the implications of these new records for our understanding of stratiomyomorphan ecomorphology in deep time as well as their palaeoecology.


2016 ◽  
Vol 371 (1685) ◽  
pp. 20150287 ◽  
Author(s):  
Graham E. Budd ◽  
Illiam S. C. Jackson

Simulation studies of the early origins of the modern phyla in the fossil record, and the rapid diversification that led to them, show that these are inevitable outcomes of rapid and long-lasting radiations. Recent advances in Cambrian stratigraphy have revealed a more precise picture of the early bilaterian radiation taking place during the earliest Terreneuvian Series, although several ambiguities remain. The early period is dominated by various tubes and a moderately diverse trace fossil record, with the classical ‘Tommotian’ small shelly biota beginning to appear some millions of years after the base of the Cambrian at ca 541 Ma. The body fossil record of the earliest period contains a few representatives of known groups, but most of the record is of uncertain affinity. Early trace fossils can be assigned to ecdysozoans, but deuterostome and even spiralian trace and body fossils are less clearly represented. One way of explaining the relative lack of clear spiralian fossils until about 536 Ma is to assign the various lowest Cambrian tubes to various stem-group lophotrochozoans, with the implication that the groundplan of the lophotrochozoans included a U-shaped gut and a sessile habit. The implication of this view would be that the vagrant lifestyle of annelids, nemerteans and molluscs would be independently derived from such a sessile ancestor, with potentially important implications for the homology of their sensory and nervous systems.


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