Early Holocene turnover, followed by Stability, in a Caribbean lizard assemblage

Understanding how communities are impacted by environmental perturbations is integral for addressing the ongoing biodiversity crisis that impacts ecosystems worldwide. The fossil record serves as a window into ancient interactions and the responses of communities to past perturbations. Here, we re-examine paleontological data from Katouche Bay, Anguilla, a Holocene site in the Lesser Antilles. We reveal that the site was more diverse than previously indicated, with long-term, continuous records of three genera of extant lizards (Anolis, Ameiva, and Thecadactylus), and the early Holocene presence of Leiocephalus, a large ground-dwelling lizard that has since been completely extirpated from the Lesser Antilles. The disappearance of Leiocephalus from Katouche Bay resulted in high turnover, decreased evenness, and decreased species richness—a trend that continues to the present day. Our body size reconstructions for the most abundant genus, Anolis, are consistent with the presence of only one species, Anolis cf. gingivinus, at Katouche Bay throughout the Holocene, contrary to previously published studies. Additionally, we find no evidence of dwarfism in A. cf. gingivinus, which contrasts with a global study of contemporary insular lizards. Our data reveal that the impacts of diversity loss on lizard communities are long lasting and irreversible over millennia.

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Estimating the effects of sampling biases on pterosaur diversity patterns: implications for hypotheses of bird/pterosaur competitive replacement

Paleobiology ◽

10.1666/0094-8373-35.3.432 ◽

2009 ◽

Vol 35 (3) ◽

pp. 432-446 ◽

Cited By ~ 85

Author(s):

Richard J. Butler ◽

Paul M. Barrett ◽

Stephen Nowbath ◽

Paul Upchurch

Keyword(s):

Species Richness ◽

Fossil Record ◽

Phylogenetic Diversity ◽

Detailed Examination ◽

Causal Mechanism ◽

Strongly Correlated ◽

Diversity Patterns ◽

Ecological Radiation ◽

Diversity Estimates

Pterosaurs were the first flying vertebrates and formed important components of terrestrial and marginal marine ecosystems during the Mesozoic. They became extinct during the latest Cretaceous (latest Maastrichtian), at, or near, the Cretaceous/Paleogene boundary, following an apparent decline in diversity in the Late Cretaceous. This reduction in species richness has been linked to the ecological radiation of birds in the Early Cretaceous and the proposal that birds competitively excluded pterosaurs from many key niches. However, although competition is often posited as a causal mechanism for many of the clade-clade replacements observed in the fossil record, these hypotheses are rarely tested. Here we present a detailed examination of pterosaur diversity through time, including both taxic and phylogenetically corrected diversity estimates and comparison of these estimates with a model describing temporal variation in the number of pterosaur-bearing formations (a proxy for rock availability). Both taxic and phylogenetic diversity curves are strongly correlated with numbers of pterosaur-bearing formations, suggesting that a significant part of the signal contained within pterosaur diversity patterns may be controlled by geological and taphonomic megabiases rather than macroevolutionary processes. There is no evidence for a long-term decline in pterosaur diversity through the Cretaceous, although a reduction in morphological, ecological, and phylogenetic diversity does appear to have occurred in the latest Cretaceous. Competitive replacement of pterosaurs by birds is difficult to support on the basis of diversity patterns.

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The preservation potential of terrestrial biogeographic patterns

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2020.2927 ◽

2021 ◽

Vol 288 (1945) ◽

pp. 20202927

Author(s):

Simon A. F. Darroch ◽

Danielle Fraser ◽

Michelle M. Casey

Keyword(s):

Fossil Record ◽

Biodiversity Loss ◽

Biodiversity Crisis ◽

Biogeographic Patterns ◽

Spatially Explicit Models ◽

Geological Past ◽

Preservation Potential ◽

Richness Patterns ◽

Extinction Events

Extinction events in the geological past are similar to the present-day biodiversity crisis in that they have a pronounced biogeography, producing dramatic changes in the spatial distributions of species. Reconstructing palaeobiogeographic patterns from fossils therefore allows us to examine the long-term processes governing the formation of regional biotas, and potentially helps build spatially explicit models for future biodiversity loss. However, the extent to which biogeographic patterns can be preserved in the fossil record is not well understood. Here, we perform a suite of simulations based on the present-day distribution of North American mammals, aimed at quantifying the preservation potential of beta diversity and spatial richness patterns over extinction events of varying intensities, and after applying a stepped series of taphonomic filters. We show that taphonomic biases related to body size are the biggest barrier to reconstructing biogeographic patterns over extinction events, but that these may be compensated for by both the small mammal record preserved in bird castings, as well as range expansion in surviving species. Overall, our results suggest that the preservation potential of biogeographic patterns is surprisingly high, and thus that the fossil record represents an invaluable dataset recording the changing spatial distribution of biota over key intervals in Earth History.

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Environmental Perturbations, Behavioral Change, and Population Response in a Long-term Northern Elephant Seal Study

10.21236/ada541689 ◽

2010 ◽

Author(s):

Daniel P. Costa

Keyword(s):

Behavioral Change ◽

Elephant Seal ◽

Northern Elephant Seal ◽

Population Response ◽

Environmental Perturbations

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Environmental Perturbations, Behavioral Change, and Population Response in a Long-Term Northern Elephant Seal Study

10.21236/ada617695 ◽

2014 ◽

Author(s):

Daniel P. Costa

Keyword(s):

Behavioral Change ◽

Elephant Seal ◽

Northern Elephant Seal ◽

Population Response ◽

Environmental Perturbations

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Getting the Most From Surveys: How Method Selection and Method Modification Impact Butterfly Survey Data

Annals of the Entomological Society of America ◽

10.1093/aesa/saab004 ◽

2021 ◽

Author(s):

Katherine C Kral-O’Brien ◽

Adrienne K Antonsen ◽

Torre J Hovick ◽

Ryan F Limb ◽

Jason P Harmon

Keyword(s):

Species Richness ◽

New Species ◽

Count Data ◽

Distance Sampling ◽

Line Transect ◽

Similar Species ◽

Method Selection ◽

M 10 ◽

Sampling Procedures

Abstract Many methods are used to survey butterfly populations, with line transect and area surveys being prominent. Observers are typically limited to search within 5 or 10 m from the line, while observers are unrestricted in larger specified search regions in area surveys. Although methods differ slightly, the selection is often based on producing defendable data for conservation, maximizing data quality, and minimizing effort. To guide method selection, we compared butterfly surveys using 1) line versus area methods and 2) varying width transects (5 m, 10 m, or unrestricted) using count data from surveys in North Dakota from 2015 to 2018. Between line and area surveys, we detected more individuals with area surveys, even when accounting for effort. However, both methods accumulated new species at similar rates. When comparing transect methodology, we detected nearly 60% more individuals and nine more species when transect width increased from 5 m to unrestricted, despite similar effort across methodology. Overall, we found line surveys slightly less efficient at detecting individuals, but they collected similar species richness to area surveys when accounting for effort. Additionally, line surveys allow the use of unrestricted-width transects with distance sampling procedures, which were more effective at detecting species and individuals while providing a means to correct count data over the same transect length. Methods that reduce effort and accurately depict communities are especially important for conservation when long-term datasets are unavailable.

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Long-term effects of abrupt environmental perturbations in model of group chase and escape with the presence of non-conservative processes

Physica A Statistical Mechanics and its Applications ◽

10.1016/j.physa.2021.126156 ◽

2021 ◽

pp. 126156

Author(s):

J.R. Šćepanović ◽

Z.M. Jakšić ◽

Lj. Budinski-Petković ◽

S.B. Vrhovac

Keyword(s):

Long Term Effects ◽

Environmental Perturbations

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Fossil Record of Parasitism on Marine Invertebrates with Special Emphasis on the Platyceratid-Crinoid Interaction

The Paleontological Society Papers ◽

10.1017/s1089332600001091 ◽

2002 ◽

Vol 8 ◽

pp. 195-210 ◽

Cited By ~ 33

Author(s):

Tomasz K. Baumiller ◽

Forest J. Gahn

Keyword(s):

Fossil Record ◽

Marine Invertebrates ◽

Marine Diversity ◽

Parasitic Interactions ◽

Explicit Criteria ◽

Lower Frequencies

The paleontological literature on marine invertebrates is rich in supposed examples of parasitism and our tabulation shows a nearly even distribution of reported cases through the post-Cambrian Phanerozoic. Slightly lower frequencies characterize the Triassic and Jurassic and higher frequencies the Cretaceous and Tertiary, and the pattern roughly mirrors Sepkoski's (1984) marine diversity curve. The total number of parasitic associations for any geologic period rarely exceeds a dozen, yet few of the reported examples provide explicit criteria distinguishing parasitism from predation, commensalism, or mutualism. We evaluated the published examples using the following criteria: (1) evidence of a long-term relationship between two organisms, (2) benefit of interaction to supposed parasite, and (3) detriment of interaction to the host We found that only in exceptional cases were these criteria fulfilled. One example that provides much information on parasitic interactions involves platyceratids and crinoids and we summarize the evidence for the parasitic interaction between these two groups of organisms.

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RETAILER’S SLOGAN IN THE FUNCTION OF PRICE IMAGE

10.31410/eman.2021.467 ◽

2021 ◽

Author(s):

Jelena Franjković ◽

Keyword(s):

Competitive Advantage ◽

Significant Role ◽

Price Level ◽

Marketing Mix ◽

Consumer Perception ◽

Successful Management ◽

High Turnover ◽

And Control ◽

Price Image

The image of the retail brand and the price image of the retailer are of significant importance for achieving a competitive advantage and long-term strengthening of the overall image. Retailers’ slogans should reflect their overall strategy and facilitate and consolidate the desired positioning in the minds of customers, ie consumers. The paper studies retailers with predominantly food products, i.e., high-turnover products. Retailers who sell products of different brands find it more difficult to manage and control the positioning of their brand, and the price image also plays a significant role in this. This paper aims to investigate and compare consumer perception of retailers’ slogans and their price image. A primary survey was conducted with persons participating in the purchase of groceries for their household and included the top five retailers in the Croatian market. The results showed that the slogan of retailers can play an important role in the successful management of the price image. The compliance of the perception of the price image of retailers by the respondents with the associations of their slogans to the price level was noted. Finally, it is concluded that the harmonization of all elements of the retail marketing mix facilitates and strengthens the desired positioning in the minds of consumers, and thus the price image.

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