Evolution, diversity, and disparity of the tiger shark lineage Galeocerdo in deep time

Abstract Sharks have a long and rich fossil record that consists predominantly of isolated teeth due to the poorly mineralized cartilaginous skeleton. Tiger sharks (Galeocerdo), which represent apex predators in modern oceans, have a known fossil record extending back into the early Eocene (ca. 56 Ma) and comprise 22 recognized extinct and one extant species to date. However, many of the fossil species remain dubious, resulting in a still unresolved evolutionary history of the tiger shark genus. Here, we present a revision of the fossil record of Galeocerdo by examining the morphological diversity and disparity of teeth in deep time. We use landmark-based geometric morphometrics to quantify tooth shapes and qualitative morphological characters for species discrimination. Employing this combined approach on fossil and extant tiger shark teeth, our results only support six species to represent valid taxa. Furthermore, the disparity analysis revealed that diversity and disparity are not implicitly correlated and that Galeocerdo retained a relatively high dental disparity since the Miocene despite its decrease from four to one species. With this study, we demonstrate that the combined approach of quantitative geometric morphometric techniques and qualitative morphological comparisons on isolated shark teeth provides a useful tool to distinguish between species with highly similar tooth morphologies.

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Spider crabs of the Western Atlantic with special reference to fossil and some modern Mithracidae

PeerJ ◽

10.7717/peerj.1301 ◽

2015 ◽

Vol 3 ◽

pp. e1301 ◽

Cited By ~ 12

Author(s):

Adiël A. Klompmaker ◽

Roger W. Portell ◽

Aaron T. Klier ◽

Vanessa Prueter ◽

Alyssa L. Tucker

Keyword(s):

Fossil Record ◽

Early Pleistocene ◽

Caribbean Region ◽

Deep Time ◽

Western Atlantic ◽

Extant Species ◽

Length Width ◽

The Caribbean ◽

Abundance And Diversity ◽

First Time

Spider crabs (Majoidea) are well-known from modern oceans and are also common in the western part of the Atlantic Ocean. When spider crabs appeared in the Western Atlantic in deep time, and when they became diverse, hinges on their fossil record. By reviewing their fossil record, we show that (1) spider crabs first appeared in the Western Atlantic in the Late Cretaceous, (2) they became common since the Miocene, and (3) most species and genera are found in the Caribbean region from the Miocene onwards. Furthermore, taxonomic work on some modern and fossil Mithracidae, a family that might have originated in the Western Atlantic, was conducted. Specifically,Maguimithraxgen. nov. is erected to accommodate the extant speciesDamithrax spinosissimus, whileDamithraxcf.pleuracanthusis recognized for the first time from the fossil record (late Pliocene–early Pleistocene, Florida, USA). Furthermore, two new species are described from the lower Miocene coral-associated limestones of Jamaica (Mithrax arawakumsp. nov. andNemausa windsoraesp. nov.). Spurred by a recent revision of the subfamily, two known species from the same deposits are refigured and transferred to new genera:Mithrax donovanitoNemausa, andMithrax unguistoDamithrax. The diverse assemblage of decapods from these coral-associated limestones underlines the importance of reefs for the abundance and diversity of decapods in deep time. Finally, we quantitatively show that these crabs possess allometric growth in that length/width ratios drop as specimens grow, a factor that is not always taken into account while describing and comparing among taxa.

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Exploring macroevolution using modern and fossil data

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.0569 ◽

2015 ◽

Vol 282 (1810) ◽

pp. 20150569 ◽

Cited By ~ 29

Author(s):

Michael J. Benton

Keyword(s):

Species Diversity ◽

Fossil Record ◽

Morphological Diversity ◽

Phylogenetic Comparative Methods ◽

Deep Time ◽

Time Patterns ◽

And Function ◽

Step Over ◽

Fossil Data ◽

Numerical Approaches

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.

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The fossil record of Ceratophrys Wied-Neuwied (Anura: Ceratophryidae): a revision and update of fossil South American horned frogs

Zootaxa ◽

10.11646/zootaxa.4658.1.2 ◽

2019 ◽

Vol 4658 (1) ◽

pp. 37-68

Author(s):

LAURA NICOLI

Keyword(s):

Fossil Record ◽

South American ◽

Unique Combination ◽

Fossil Species ◽

Environmental Tolerance ◽

Pampean Region ◽

Fossil Material ◽

Extant Species ◽

Present Distribution ◽

Living Species

Ceratophrys is the most diverse and widely distributed genus of Ceratophryidae, the clade of South American horned frogs. Numerous anuran fossil remains, including several fossil species, have been assigned to this genus. However, this seemingly extensive fossil record is problematic because several of the fossils are not properly identified and most of the taxonomic assignations are not justified. The present study traces all the fossil material attributed to Ceratophrys, clarifying, when possible, institutional allocations. Each of the remains was examined and its taxonomic assignation revisited, based on the morphology and possible synapomorphies of the genus, including its living species. Numerous fossils were properly identified and assigned with certainty to Ceratophrys. Only one fossil species, Ceratophrys ameghinorum, is considered valid. This information, along with recently reported evidence of fossil Ceratophrys, is briefly summarized to serve as a practical reference for the entire known fossil record of the genus. The fossil record is not especially informative about the evolution or distribution pattern of Ceratophrys, because most of the remains are relatively young (post-Miocene), collected within the present distribution of the genus, and morphologically consistent with that of the extant species. However, some useful information has emerged. The presence of Ceratophrys is well documented since the Neogene in the Pampean Region of South America. The single valid fossil species, Ceratophrys ameghinorum, possesses a unique combination of characters that reflects a mixture of characters observed in different clades of the genus; thus, resolution of its phylogentic position will inform our understanding of the evolution of the genus. The paleoenvironmental significance of some Ceratophrys fossils is also discussed, addressing the wide, but incompletely known current distribution and environmental tolerance of the genus.

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Atypical short elytra in Cretaceous short-winged flower beetles (Coleoptera: Kateretidae)

Palaeoentomology ◽

10.11646/palaeoentomology.2.5.14 ◽

2019 ◽

Vol 2 (5) ◽

pp. 505-514 ◽

Cited By ~ 2

Author(s):

DAVID PERIS ◽

JOSEF JELÍNEK

Keyword(s):

Fossil Record ◽

Ancestral State ◽

Fossil Species ◽

Extant Species ◽

The Family

Although the family Kateretidae has fewer than 100 described extant species, its fossil record is growing. The description given here of Electrumeretes birmanicus gen. et sp. nov. and Polliniretes penalveri gen. et sp. nov. brings the number of fossil species in Kateretidae up to nine. Eight of the fossil species have been described from amber deposits and six are from the Cretaceous. All the Cretaceous fossil species and one from the Eocene share atypically short elytra and three dorsally exposed abdominal tergites, whereas in Recent relatives, even though they have shortened elytra, only the pygidium and a part of the preceding one or two abdominal tergites are exposed. It is suggested that shortened elytra (brachelytry) represents an ancestral state and that elytra may have become secondary longer in extant relatives.

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

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2015.0223 ◽

2016 ◽

Vol 371 (1691) ◽

pp. 20150223 ◽

Cited By ~ 13

Author(s):

Clive N. Trueman ◽

Ming-Tsung Chung ◽

Diana Shores

Keyword(s):

Fossil Record ◽

Temporal Trends ◽

Morphological Diversity ◽

Population Connectivity ◽

The Body ◽

Deep Time ◽

The Common ◽

Body Fossil ◽

Methodological Ground

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.

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On the probability of ancestors in the fossil record

Paleobiology ◽

10.1017/s0094837300016146 ◽

1996 ◽

Vol 22 (2) ◽

pp. 141-151 ◽

Cited By ~ 112

Author(s):

Mike Foote

Keyword(s):

Fossil Record ◽

Marine Invertebrates ◽

Fossil Species ◽

Direct Descendant ◽

Extant Species ◽

Homogeneous Models ◽

Temporal And Spatial

Three homogeneous models of species origination and extinction are used to assess the probability that ancestor-descendant pairs are preserved in the fossil record. In the model of cladogenetic budding, a species can persist after it branches and can therefore have multiple direct descendants. In the bifurcation model, a species branches to give rise to two distinct direct descendants, itself terminating in the process. In the model of phyletic transformation, a species gives rise to a single direct descendant without branching, itself terminating in the process. Assuming homogeneous preservation, even under pessimistic assumptions regarding the completeness of the fossil record, the probability of finding fossil ancestor-descendant pairs is not negligible. Even if all species of Phanerozoic marine invertebrates in the paleontologically important taxa had the same probability of preservation, on the order of 1%-10% or more of the known fossil species would be directly ancestral to other known fossil species. However, this is likely to be an underestimate, since the probability of finding ancestor-descendant pairs is enhanced by taxonomic, temporal, and spatial heterogeneities in preservation probability. Moreover, indirect genealogical relationships substantially increase the probability of finding ancestor-descendant pairs. The model of budding, the only one in which an ancestor can persist after a branching event, predicts that half or more of extant species have ancestors that are also extant. Thus, the question of how to recognize ancestor-descendant pairs must be carefully considered.

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Integrating palaeo- and archaeobotanical data for a synthesis of the Italian fossil record of Lycopus (Lamiaceae, Mentheae)

Phytotaxa ◽

10.11646/phytotaxa.513.1.1 ◽

2021 ◽

Vol 513 (1) ◽

Author(s):

EDOARDO MARTINETTO ◽

NICOLA M. G. ARDENGHI ◽

DANIELE AROBBA ◽

ADELE BERTINI ◽

GIOVANNA BOSI ◽

...

Keyword(s):

Fossil Record ◽

Ad Hoc ◽

Central Italy ◽

West Siberia ◽

Morphological Type ◽

Herbaceous Plant ◽

Fossil Species ◽

Early Oligocene ◽

Extant Species ◽

First Occurrence

Lycopus is a widespread herbaceous plant, currently part of European flora. Fossil remains of fruits (nutlets or mericarps) attributed to this genus are frequently found in European archaeological and palaeontological sites, being easily preserved in sedimentary deposits. In a worldwide context, the oldest fossils are from the early Oligocene (ca. 30 Ma) of West Siberia, but they become more common in Miocene (23.0–5.3 Ma) records, ranging from West Siberia to Central Europe. In the literature, the Oligocene and Miocene remains (plus a few Pliocene ones) were assigned to fossil-species, whereas the abundant Pliocene and Pleistocene occurrences (5–0.01 Ma) in Europe were mainly assigned to the extant species L. europaeus. The present work is conceived as the result of an ad hoc research team whose task was to revise and summarize the Italian fossil record of Lycopus, assembling palaeobotanical and archaeobotanical data. We herein report ca. 6000 Lycopus nutlets from 61 sites located in nine regions of Northern and Central Italy. Based on the available information on extant species, we detected nine morphological types of nutlets that can be used for the characterisation of fossils. Our analysis suggests that from 4 to 2.6 Ma a single taxon (L. cf. pliocenicus) with L. americanus-type of nutlets occurred in Italy. The first occurrence of the latter morphological type is from the early Oligocene of West Siberia. The available fossils mildly suggest that extant L. americanus could be the descendant of ancient Eurasian plants characterised by the L. americanus-type of nutlets, through expansion of their range to North America. Conversely, the abundant Italian records of the last 0.2 Ma, including remains from archaeological sites, are only referable to the Eurasian species L. europaeus.

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First fossil Litoleptis (Diptera: Spaniidae) from the Lower Cretaceous amber of San Just (Teruel Province, Spain)

Zootaxa ◽

10.11646/zootaxa.2026.1.3 ◽

2009 ◽

Vol 2026 (1) ◽

pp. 33-39 ◽

Cited By ~ 8

Author(s):

ANTONIO ARILLO ◽

ENRIQUE PEÑALVER ◽

VICTORIA GARCÍA-GIMENO

Keyword(s):

Lower Cretaceous ◽

Fossil Record ◽

Wing Venation ◽

Fossil Species ◽

Extant Species ◽

The Family ◽

First Time

In this paper Litoleptis fossilis sp. nov. a new fossil species belonging to the family Spaniidae (Diptera) is described. This is the first time the genus Litoleptis has been described from the fossil record. A comparison with extant species of Litoleptis and other fossil rhagionoids is done. The fossil is also compared to not closely related Diptera but having convergent wing venation. Palaeoecological and palaeobiogeographical comments are provided.

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Micromys caesaris, a new murid (Rodentia, Mammalia) from the Late Pliocene of the Guadix Basin, southeastern Spain

Journal of Paleontology ◽

10.1666/06-030.1 ◽

2008 ◽

Vol 82 (2) ◽

pp. 436-441 ◽

Cited By ~ 7

Author(s):

Raef Minwer-Barakat ◽

Antonio García-Alix ◽

Elvira Martín-Suárez ◽

Matthijs Freudenthal

Keyword(s):

Late Miocene ◽

Fossil Record ◽

Fossil Species ◽

Late Pliocene ◽

Early Pliocene ◽

Southeastern Spain ◽

Extant Species ◽

North Asia ◽

Micromys Minutus

The Genus Micromys includes a single extant species, Micromys minutus (Pallas, 1771), which lives in Europe and North Asia. This genus is known in the fossil record since the late Miocene; eight fossil species have been described in Europe and Asia, most of them of late Miocene and early Pliocene age. The evolution of this genus during the late Pliocene is barely known. Although it is present in numerous localities of this age, remains of Micromys are usually scarce and generally assigned to the species M. minutus or M. praeminutus Kretzoi, 1959.

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Eco-morphological diversity of larvae of soldier flies and their closest relatives in deep time

PeerJ ◽

10.7717/peerj.10356 ◽

2020 ◽

Vol 8 ◽

pp. e10356

Author(s):

Viktor A. Baranov ◽

Yinan Wang ◽

Rok Gašparič ◽

Sonja Wedmann ◽

Joachim T. Haug

Keyword(s):

Early Cretaceous ◽

Fossil Record ◽

New Records ◽

Morphological Diversity ◽

Baltic Amber ◽

Ecosystem Functions ◽

Deep Time ◽

Dominican Amber ◽

Species Being

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.

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