scholarly journals Morphological and molecular rates of evolution in post-Paleozoic echinoids

1992 ◽  
Vol 6 ◽  
pp. 273-273
Author(s):  
Andrew B. Smith ◽  
R. Christen
Keyword(s):  
Morphological Evolution ◽  
Large Subunit ◽  
Rank Correlation ◽  
Great Majority ◽  
Data Matrix ◽  
Time Interval ◽  
28S Rrna ◽  
Geological Time ◽  
Molecular Change ◽  
Rates Of Evolution

Phylogenetic analysis of a data matrix of 86 skeletal characteristics, and of the first 400 bases of the 5’ end of the large subunit ribosomal RNA gene produce congruent cladograms for 11 extant echinoids. Based on these cladistic analyses the great majority of morphologic and molecular apomorphies can be placed in one of 18 independent geological time intervals. When the cladogram is calibrated using the fossil record of post-Paleozoic echinoids, rates of molecular change in 28S rRNA can be calculated and compared with estimated rates of morphological evolution.Morphological and molecular apomorphies acquired in each time interval both correlate moderately strongly with time elapsed, but less strongly with one another. As expected, morphological rates vary considerably over time and between sister groups, but so too do molecular rates. When averaged over all echinoids studied, the number of morphological apomorphies accrued yields a slightly higher Spearman Rank correlation coefficient with time elapsed than does the number of molecular apomorphies accrued. This is because there is a three-fold difference in the rate of molecular change amongst the echinoid lineages studied.

Comparative variation of morphological and molecular evolution through geologic time: 28 S ribosomal RNA versus morphology in echinoids

1992 ◽  
Vol 338 (1286) ◽  
pp. 365-382 ◽  
Keyword(s):  
Molecular Evolution ◽  
Maximum Likelihood ◽  
Morphological Change ◽  
Rank Correlation ◽  
Morphological Data ◽  
Parsimony Analysis ◽  
Geological Time ◽  
Molecular Changes ◽  
Molecular Change ◽  
Rates Of Evolution

The comparatively good fossil record of post-Palaeozoic echinoids allows rates of morphological change to be estimated over the past 260 million years and com pared with rates of molecular evolution. Parsimony analysis of morphological data, based predominantly on skeletal characteristics, and parsimony, distance and maximum likelihood analyses of molecular data, from the first 380 bases from the 5' end of the 28 S rRNA molecule, for 10 species of echinoid produce congruent phylogenies. The m olecular sequence chosen is dem onstrably far from saturation and sister groups have divergence times ranging from about 15 to 260 Ma. Parsimony analysis allows the great majority of molecular and morphological apomorphies to be placed in one of 18 independent geological time intervals, providing a direct measure of rates of evolution for periods in the geological past. Because most molecular fixed point m utations in our sequences cannot be polarized unambiguously by outgroup comparison (making the outgroup states effectively random), distance and parsimony analyses both tend spuriously to root the echinoid tree on the longest internal branch. A topology identical to that derived from morphological data is, however, obtained using Maximum Likelihood and also parsimony analysis where outgroup rooting is restricted to more conserved regions. This is taken as the correct topology for assessing rates of evolution. Overall, both morphological and molecular changes show a m oderately strong correlation with time elapsed, but a weaker correlation with one another. Statistically significant differences in evolutionary rate are found between some, but not all, pair-wise comparisons of sister lineages for both molecular and morphological data. The molecular clock rate for echinaceans is three times faster than that for cidaroids and irregular echinoids. Spearm an’s rank correlation test, which requires only relative m agnitude of changes to be known, suggests that morphological change has a slightly better correlation with time than does molecular change, averaged over all ten species. However, when just echinaceans are considered an extremely good correlation is found between the num ber of molecular changes and time elapsed, whereas morphological change remains poorly correlated. Thus, molecular rates approxim ate to a clocklike model within restricted echinoid elades, but vary significantly between clades. Averaging results over all echinoids produces a correlation that is no better than the correlation between morphological change and time elapsed.

scholarly journals Dynamic evolutionary change in post-Paleozoic echinoids and the importance of scale when interpreting changes in rates of evolution

2015 ◽  
Vol 112 (12) ◽  
pp. 3758-3763 ◽  
Author(s):  
Melanie J. Hopkins ◽  
Andrew B. Smith
Keyword(s):  
Initial Phase ◽  
Evolutionary History ◽  
Morphological Evolution ◽  
Morphological Diversity ◽  
Feeding Strategies ◽  
Geological Time ◽  
Internal Constraints ◽  
Rates Of Evolution ◽  
History Of ◽  
Morphological Innovation

How ecological and morphological diversity accrues over geological time has been much debated by paleobiologists. Evidence from the fossil record suggests that many clades reach maximal diversity early in their evolutionary history, followed by a decline in evolutionary rates as ecological space fills or due to internal constraints. Here, we apply recently developed methods for estimating rates of morphological evolution during the post-Paleozoic history of a major invertebrate clade, the Echinoidea. Contrary to expectation, rates of evolution were lowest during the initial phase of diversification following the Permo-Triassic mass extinction and increased over time. Furthermore, although several subclades show high initial rates and net decreases in rates of evolution, consistent with “early bursts” of morphological diversification, at more inclusive taxonomic levels, these bursts appear as episodic peaks. Peak rates coincided with major shifts in ecological morphology, primarily associated with innovations in feeding strategies. Despite having similar numbers of species in today’s oceans, regular echinoids have accrued far less morphological diversity than irregular echinoids due to lower intrinsic rates of morphological evolution and less morphological innovation, the latter indicative of constrained or bounded evolution. These results indicate that rates of evolution are extremely heterogenous through time and their interpretation depends on the temporal and taxonomic scale of analysis.

scholarly journals Cladistics and rates of morphological evolution: computation and comparison

1992 ◽  
Vol 6 ◽  
pp. 61-61
Author(s):  
Richard Cloutier ◽  
Timothy Rowe
Keyword(s):  
Morphological Evolution ◽  
Average Rate ◽  
Relative Rate ◽  
Phylogenetic Analyses ◽  
Evolutionary Rates ◽  
Data Matrix ◽  
Morphological Data ◽  
Geological Time Scale ◽  
Rates Of Evolution ◽  
Wide Range

For the part fifty years, the concept of evolutionary rates has been developed largely in an evolutionary or phenetic framework. Many authors discussed rates, but under previous systematic paradigms no standardized methods developed to provide a uniform and general framework in which temporal properties of different lineages could be objectively measured and compared.We review recently developed methods for measuring rate-related properties of lineages that are based on phylogenetic analyses. Rate measurements are made directly from phylogenetic data matrices and cladograms. Because they benefit from the standardized procedures required to compile a data matrix, these methods are potentially exportable to a wide range of phylogenetic studies. Four potential factors relevant to the study of evolutionary rates in a cladistic framework have been analyzed with these methods: (1) morphological changes, (2) age and duration, (3) cladogenesis, and (4) species-diversity. We investigate interactions among these factors.Underlying assumptions in using a cladogram to calculate rates of evolution are: (1) the tree reflects the history of the group, and (2) the distributions of character states on the tree reflects the true distribution of character states during the evolution of the group. The calculation of rates from a cladogram requires that: (1) the cladograms are derived from parsimony analysis (e.g., PAUP, HENNIG86) of species coded for discrete character states; (2) the phylogenetic pattern (or branching sequence) is superimposed on a geological time scale in which each species is mapped according to its geological age (temporal cladogram); (3) phylogenetic pathways (unidirectional series of consecutive cladogenetic events) are determined in such a manner that the selected origin is a hypothetical ancestor to the terminal taxa selected; and (4) rates are calculated along selected phylogenetic pathways.Rates may be calculated as the number of changes—including autapomorphies, synapomorphies, and homoplasies—per unit of time. Alternatively, relative measures of rate may be obtained by comparing the average number of changes for an entire data matrix with changes in data subsets within the matrix. Five types of rates of morphological evolution can be determined and quantified along a phylogenetic pathway: (1) rate between two consecutive cladogenetic events, (2) rate during a geological period, (3) rate during a fixed period of time in millions of years, (4) relative rates of change for different morphological data subsets, such as dentition versus skeleton, and (5) relative rate along a selected segment of the cladogram, compared to the average rate measured for the cladogram as a whole. Various methods for comparing rates are investigated, such as Spearman Rank correlation, Fourier analysis, time series, and homoplasy index.Classic examples of rates of morphological evolution were previously taken from bivalves, echinoderms, lungfishes, coelacanths, and mammals. In the present study, rates of evolution within and/or between the Dipnoi (lungfishes), the Actinistia (coelacanths), and the Mammalia are calculated and compared.

scholarly journals Biomechanical trade-offs bias rates of evolution in the feeding apparatus of fishes

2011 ◽  
Vol 279 (1732) ◽  
pp. 1287-1292 ◽  
Author(s):  
Roi Holzman ◽  
David C. Collar ◽  
Samantha A. Price ◽  
C. Darrin Hulsey ◽  
Robert C. Thomson ◽  
...  
Keyword(s):  
Genetic Factors ◽  
Morphological Evolution ◽  
The Body ◽  
Body Parts ◽  
Phenotypic Evolution ◽  
Genetic Constraints ◽  
Functional Systems ◽  
Rates Of Evolution ◽  
Trade Offs

Morphological diversification does not proceed evenly across the organism. Some body parts tend to evolve at higher rates than others, and these rate biases are often attributed to sexual and natural selection or to genetic constraints. We hypothesized that variation in the rates of morphological evolution among body parts could also be related to the performance consequences of the functional systems that make up the body. Specifically, we tested the widely held expectation that the rate of evolution for a trait is negatively correlated with the strength of biomechanical trade-offs to which it is exposed. We quantified the magnitude of trade-offs acting on the morphological components of three feeding-related functional systems in four radiations of teleost fishes. After accounting for differences in the rates of morphological evolution between radiations, we found that traits that contribute more to performance trade-offs tend to evolve more rapidly, contrary to the prediction. While ecological and genetic factors are known to have strong effects on rates of phenotypic evolution, this study highlights the role of the biomechanical architecture of functional systems in biasing the rates and direction of trait evolution.

scholarly journals Estimation of the total magnetization direction of approximately spherical bodies

2014 ◽  
Vol 1 (2) ◽  
pp. 1465-1507
Author(s):  
V. C. Oliveira ◽  
D. P. Sales ◽  
V. C. F. Barbosa ◽  
L. Uieda
Keyword(s):  
Synthetic Data ◽  
Magnetization Vector ◽  
Spherical Shape ◽  
Time Interval ◽  
Alkaline Complex ◽  
Multiple Sources ◽  
Geological Time ◽  
Magnetization Direction ◽  
Reduction To The Pole ◽  
Horizontal Grid

Abstract. We have developed a fast total-field anomaly inversion to estimate the magnetization direction of multiple sources with approximately spherical shape and known centres. Our method can be applied to interpret multiple sources with different magnetization directions. It neither requires the prior computation of any transformation like reduction to the pole nor the use of regularly spaced data on a horizontal grid. The method contains flexibility to be implemented as a linear or non-linear inverse problem, which results, respectively, in a least-squares or robust estimate of the components of the magnetization vector of the sources. Applications to synthetic data show the robustness of our method against interfering anomalies and errors in the location of the sources' centre. Besides, we show the feasibility of applying the upward continuation to interpret non-spherical sources. Applications to field data over the Goiás Alkaline Province (GAP), Brazil, show the good performance of our method in estimating geological meaningful magnetization directions. The results obtained for a region of the GAP, near from the alkaline complex of Diorama, suggest the presence of non-outcropping sources marked by strong remanent magnetization with inclination and declination close to -70.35° and -19.81°, respectively. This estimated magnetization direction leads to predominantly positive reduced-to-the-pole anomalies, even for other region of the GAP, in the alkaline complex of Montes Claros de Goiás. These results show that the non-outcropping sources near from the alkaline complex of Diorama have almost the same magnetization direction of that ones in the alkaline complex of Montes Claros de Goiás, strongly suggesting that these sources have emplaced the crust almost within the same geological time interval.

scholarly journals Ecomorphological diversification in squamates from conserved pattern of cranial integration

2019 ◽  
Vol 116 (29) ◽  
pp. 14688-14697 ◽  
Author(s):  
Akinobu Watanabe ◽  
Anne-Claire Fabre ◽  
Ryan N. Felice ◽  
Jessica A. Maisano ◽  
Johannes Müller ◽  
...  
Keyword(s):  
Morphological Evolution ◽  
Habitat Preferences ◽  
Reproductive Mode ◽  
Phenotypic Integration ◽  
Common Pattern ◽  
Skull Shape ◽  
Rates Of Evolution ◽  
Rapid Changes ◽  
Developmental Variations ◽  
Jaw Musculature

Factors intrinsic and extrinsic to organisms dictate the course of morphological evolution but are seldom considered together in comparative analyses. Among vertebrates, squamates (lizards and snakes) exhibit remarkable morphological and developmental variations that parallel their incredible ecological spectrum. However, this exceptional diversity also makes systematic quantification and analysis of their morphological evolution challenging. We present a squamate-wide, high-density morphometric analysis of the skull across 181 modern and extinct species to identify the primary drivers of their cranial evolution within a unified, quantitative framework. Diet and habitat preferences, but not reproductive mode, are major influences on skull-shape evolution across squamates, with fossorial and aquatic taxa exhibiting convergent and rapid changes in skull shape. In lizards, diet is associated with the shape of the rostrum, reflecting its use in grasping prey, whereas snakes show a correlation between diet and the shape of posterior skull bones important for gape widening. Similarly, we observe the highest rates of evolution and greatest disparity in regions associated with jaw musculature in lizards, whereas those forming the jaw articulation evolve faster in snakes. In addition, high-resolution ancestral cranial reconstructions from these data support a terrestrial, nonfossorial origin for snakes. Despite their disparate evolutionary trends, lizards and snakes unexpectedly share a common pattern of trait integration, with the highest correlations in the occiput, jaw articulation, and palate. We thus demonstrate that highly diverse phenotypes, exemplified by lizards and snakes, can and do arise from differential selection acting on conserved patterns of phenotypic integration.

Testing for equality of rates of evolution

Paleobiology ◽  
1987 ◽  
Vol 13 (3) ◽  
pp. 272-285 ◽  
Author(s):  
Jennifer A. Kitchell ◽  
George Estabrook ◽  
Norman MacLeod
Keyword(s):  
Rapid Change ◽  
Time Interval ◽  
Data Sets ◽  
Independent Data ◽  
Change Rate ◽  
Rates Of Evolution ◽  
Generative Processes ◽  
Pattern Of Variation ◽  
Ordered Data ◽  
Post Hoc

A new method of data analysis offers a potentially powerful tool for statistically evaluating hypotheses of rate in temporally-ordered evolutionary phenomena. We present a method for bootstrapping time-ordered data sets to test hypotheses of the equality of rate. This method is applicable to both nonrandom and random generative processes. The method is applied to the data of Malmgren et al. (1983) for the Globorotalia plesiotumida–G. tumida planktonic foraminiferan lineage and the data of Reyment (1982) for the benthonic foraminiferan Afrobolivina afar. G. plesiotumida is recognizable on the basis of independent data as a species distinct from G. tumida, its descendant. Evolutionary change rate during the evolution of G. tumida from G. plesiotumida is shown to be faster than rates within either species. The pattern of variation exhibited by A. afar includes a time interval of more rapid change; this more rapid change is observed post hoc. A bootstrapping model based on post hoc observations reveals the rate in this time interval to be not significantly faster than expected in such post hoc intervals.

Gyrothyris williamsi sp. nov. and inter-relationships of some taxa from waters around New Zealand and the southern oceans (Rhynchonelliformea: Terebratelloidea)

2007 ◽  
Vol 98 (3-4) ◽  
pp. 425-435 ◽  
Author(s):  
Maria Aleksandra Bitner ◽  
Bernard L. Cohen ◽  
Sarah. L. Long ◽  
Bertrand Richer de Forges ◽  
Michiko Saito
Keyword(s):  
New Zealand ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Phylogenetic Reconstruction ◽  
Sister Group ◽  
Last Common Ancestor ◽  
Rdna Sequences ◽  
Sw Pacific ◽  
Rates Of Evolution ◽  
The Antarctic

ABSTRACTThis paper describes a terebratelloid articulate brachiopod, Gyrothyris williamsi sp. nov., based on 95 specimens from seamounts on the Lord Howe Rise, Coral Sea, SW Pacific Ocean. The new species is attributed to Gyrothyris on the basis of (a) morphological and growth trajectory similarities; (b) phylogenetic analyses of an alignment of DNA sequence (∼2900-sites) obtained from nuclear-encoded small- and large-subunit ribosomal RNA genes (SSU and LSU); and (c) the presence of a distinctive, two-part deletion in the LSU gene. It is distinguished morphologically from Gyrothyris mawsoni and its subspecies by both internal and external morphology and by its isolated geographical distribution, which extends the patchy, known range of this genus to an area some 2000 km north of its previous northern limit around New Zealand. Phylogenetic analyses of the rDNAs and of mitochondrial cox1 gene sequences (663 sites) confirm previous indications that the New Zealand endemic terebratelloid genera form a clade (Neothyris (Calloria, Gyrothyris, Terebratella), but the position of Terebratella with respect to Calloria and Gyrothyris remains weakly established. These sequences disagree inexplicably about the closeness of the relationship between Neothyris parva and N. lenticularis. Analyses of the first sequences from Calloria variegata, a species restricted to the Hauraki Gulf, New Zealand, are consistent with the possibility that it originated locally, and recently, from C. inconspicua. Magellania venosa from S. America/Falklands joins with Antarctic Magellania fragilis and M. joubini to form an rDNA clade that excludes Terebratalia as the putative sister-group of the New Zealand terebratelloid clade. The cox1 (but not the rDNA) sequences of the New Zealand clade pass a test for clock-like rates of evolution, and maximum likelihood pairwise distances suggest that if genetic isolation between the ancestor of Antarctic Magellania and the last common ancestor of the New Zealand terebratelloid clade was initiated by separation of the Antarctic and New Zealand plates ∼90 Mya, isolation from M. venosa was initiated earlier, perhaps ∼145 Mya. However, in the simple phylogenetic reconstruction presented here from cox1 sequences, S. American and Antarctic Magellania spp. do not yield a well-supported clade, perhaps because of differences in base composition.

From 18S ribosomal sequence data to evolution of morphology among the fungi

1995 ◽  
Vol 73 (S1) ◽  
pp. 677-683 ◽  
Author(s):  
Mary L. Berbee ◽  
John W. Taylor
Keyword(s):  
Sequence Data ◽  
Morphological Evolution ◽  
Strong Support ◽  
Morphological Characters ◽  
Geological Time ◽  
Data Set ◽  
Dna Sequence Data ◽  
Sequence Of Events ◽  
History Of ◽  
Time Of Divergence

From ribosomal DNA sequence data we can estimate ascomycete relationships, the time of divergence of major ascomycete lineages, and the history of morphological evolutionary change. Groups long accepted by mycologists such as the filamentous ascomycetes with fruiting bodies, (the plectomycetes and pyrenomycetes) are supported by 18S rDNA sequence data. After generating a phylogenetic tree showing relationships, the geological time of divergence of major fungal lineages may be estimated, inferring elapsed time using the calibrated percent substitutions between sequences. Determining the pathway of evolution of morphological characters is more difficult than inferring the relationships among these taxa. To establish the history of morphological evolution, we need accurate trees receiving strong support from our data set. We also need taxa with the intermediate characters to reveal the sequence of events in morphological evolution. Soon, however, we may be able to take a more direct approach to evolution of morphological characters, sequencing the genes that code for the character. Key words: fungus evolution, ascomycete phylogeny.

scholarly journals Rates of morphological evolution in Captorhinidae: An adaptive radiation of Permian herbivores

2017 ◽  
Author(s):  
Neil Brocklehurst
Keyword(s):  
Causal Relationship ◽  
Adaptive Radiation ◽  
Morphological Evolution ◽  
Morphological Characteristics ◽  
Terrestrial Ecosystems ◽  
Evolutionary Patterns ◽  
Evolutionary Innovation ◽  
Rates Of Evolution ◽  
Key Innovation ◽  
The Impact

The evolution of herbivory in early tetrapods was crucial in the establishment of terrestrial ecosystems, although it is so far unclear what effect this innovation had on the macro-evolutionary patterns observed within this clade. The clades which entered this under-filled region of ecospace might be expected to have experienced an “adaptive radiation”: an increase in rates of morphological evolution and speciation driven by the evolution of a key innovation. However such inferences are often circumstantial, being based on the coincidence of a rate shift with the origin of an evolutionary novelty. The conclusion of an adaptive radiation may be made more robust by examining the pattern of the evolutionary shift; if the evolutionary innovation coincides not only with a shift in rates of morphological evolution, but specifically in the morphological characteristics relevant to the ecological shift of interest, then one may more plausibly infer a causal relationship between the two. Here I examine the impact of diet evolution on rates of morphological change in one of the earliest tetrapod clades to evolve high-fibre herbivory: Captorhinidae. Using a method of calculating heterogeneity in rates of discrete character change across a phylogeny, it is shown that a significant increase in rates of evolution coincides with the transition to herbivory in captorhinids. Theherbivorous captorhinids also exhibit greater morphological disparity than their faunivorous relatives, indicating more rapid exploration of new regions of morphospace. As well as an increase in rates of evolution, there is a shift in the regions of the skeleton undergoing the most change; the character changes in the herbivorous lineages are concentrated in the manible and dentition. The fact that the increase in rates of evolution coincides with increased change in characters relating to food acquisition provides stronger evidence for a causal relationship between the herbivorous diet and the radiation event.

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