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Journal Article
Mateus, O. (2008).  Two ornithischian dinosaurs renamed: Microceratops Bohlin 1953 and Diceratops Lull 1905. Journal of Paleontology. 82, 423., Number 2 Abstractmateus_2008_two_ornithischians_renamed__microceratops_bohlin_1953_and_diceratops_lull_.pdfWebsite

dinosaur genera Diceratops Lull, 1905 and Microceratops Bohlin, 1953 are preoccupied by the Hymenoptera insects, Diceratops Foerster, 1868 and Microceratops Seyrig, 1952, respectively. Therefore, the name of the ceratopsian dinosaur Diceratops Lull, 1905 from the Late Cretaceous of United States is a junior homonym of the hymenoptera Diceratops Foerster, 1868. Diceratus n. gen. (Greek di ‘‘two,’’ Greek ceratos ‘‘horned’’) is proposed as the replacement name of Diceratops Lull, 1905. Some workers have considered Diceratops synonymous with Triceratops (e.g., Dodson and Currie, 1990) but it was reinstated by Forster (1996) after analysis of the characteristics of all existing ceratopsid skulls, and recent reviews (e.g., Dodson et al., 2004) have considered Diceratops a valid genus.
Due to preoccupation, the name of the ceratopsian dinosaur Microceratops Bohlin, 1953 from the Cretaceous of the Gobi is
a junior homonym of the insect Microceratops Seyrig, 1952. Microceratus n. gen. (Greek micro ‘‘small,’’ Greek ceratos ‘‘horned’’) is proposed as the replacing name of Microceratops Bohlin, 1953.
Sereno (2000:489) has declared Microceratops a nomen dubium since the holotype material lacks any diagnostic features, a
convention followed by You and Dodson (2004:480). However, the name is still used by Le Loeuff et al. (2002), Lucas (2006),
Alifanov (2003) and Xu et al. (2002), and such practice justifies the renaming of the genus.
In order to preserve some stability, the names chosen here deliberately preserve the same prefixes.

Mateus, O. (2008).  Two ornithischian dinosaurs renamed: Microceratops Bohlin 1953 and Diceratops Lull 1905. Journal of Paleontology. 82, , Number 2 Abstract
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Schulp, A. S., Polcyn M. J., Mateus O., & Jacobs L. L. (2013).  Two rare mosasaurs from the Maastrichtian of Angola and the Netherlands. Netherlands Journal of Geosciences — Geologie en Mijnbouw. 92(1), 3-10. Abstractschulp_et_al_2013_two_rare_mosasaurs_from_the_maastrichtian_of_angola__njg-92-1-schulp.pdf

We report here the addition of two rare mosasaur taxa to the Maastrichtian marine amniote fauna of Angola. The new specimens include a dentary fragment referable to the large carnivore Prognathodon saturator and an isolated tooth of the small durophage Carinodens belgicus. Both were recovered from Maastrichtian outcrops in southern Angola in 2011. Additionally, a complete posterior mandibular unit of a large mosasaur from the type Maastrichtian of The Netherlands, collected some time prior to 1879 and previously identified as ‘Mosasaurus giganteus’, is described and reassigned here to Prognathodon saturator; historical issues surrounding the taxonomic attribution of this specimen are clarified. The new material extends the known geographic distribution of Prognathodon saturator and Carinodens belgicus.

Schulp, A. S., Polcyn M. J., Mateus O., & Jacobs L. L. (2013).  Two rare mosasaurs from the Maastrichtian of Angola and the Netherlands. Geologie en Mijnbouw/Netherlands Journal of Geosciences. 92, 3-10., Number 1 Abstract
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Mateus, O., Estraviz López D., & Madeira Mateus S. G. (2022).  Type specimens alone have a strong correlation with taxa record by geological epoch: the case study of the fossil vertebrates named from {Portuguese} types. Comunicações Geológicas. 109, 57–64. Abstractmateus-et-al_2022_type_specimens.pdfWebsite

ABSTRACT: Type specimens (holotypes, neotypes, syntypes, etc.) are of crucial importance because they are the only tangible evidence of the nomenclatural act that supports the understanding of paleobiodiversity. The list of the vertebrate species whose type specimen is based on fossils from Portugal is presented here. We counted 206 species, of which there are 45 bony fishes, 39 Late Jurassic Mammaliamorpha, 33 Cenozoic mammals, 28 non-avian dinosaurs, 25 non-dinosaur reptiles, 11 Cenozoic Aves, 22 Chondrichthyes and three other vertebrates. Except for the Quaternary fossil record, the type specimens can be used as a shortcut for measuring the fossil record and paleobiodiversity through geological time and rock units because they correlate in 95% with the fossil record by epoch in the case-study of fossil vertebrates of Portugal.

Allain, R., Taquet P., Battail B., Dejax J., Richir P., Veran M., Limon-Duparcmeur F., Vacant R., Mateus O., Sayarath P., Khenthavong B., & Phouyavong S. (1999).  Un nouveau genre de dinosaure sauropode de la formation des Gres superieurs (Aptien-Albien) du Laos. Comptes Rendus de l'Academie des Sciences - Series IIA - Earth and Planetary Science. 329, 609-616., oct, Number 8 Abstractallain_taquet_battail_dejax_richir_mateus_et_al_1999_un_nouveau_genre_de_dinosaure_sauropode_de_la_formation_des_gres_superieurs_aptien-albien_du_laos.pdfWebsite

The partly-articulated postcranial remains of two sauropod skeletons recently found in Tang Vay (Savannakhet Province, Laos) are assigned to the species Tangvayosaurus hoffeti (nov. gen., nov. sp.). The derived characters present in the new material confirm the presence of titanosaurs in South East Asia at the end of the Early Cretaceous, but are not consistent with its placement within Titanosaurus genus as first done by Hoffet in 1942. All of the material relative to this species is therefore referred to a new genus: Tangvayosaurus. Tangvayosaurus and the Thai genus Phuwiangosaurus have strong affinities and are considered as primitive titanosaurs.

Allain, R., Taquet P., Battail B., Dejax J., Richir P., Véran M., Limon-Duparcmeur F., Vacant R., Mateus O., Sayarath P., Khenthavong B., & Phouyavong S. (1999).  Un nouveau genre de dinosaure sauropode de la formation des Grès supérieurs (Aptien-Albien) du Laos. Comptes Rendus de l{\textquotesingle}Académie des Sciences - Series {IIA} - Earth and Planetary Science. 329, 609–616., oct, Number 8: Elsevier {BV} AbstractWebsite
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Allain, R., Taquet P., Battail B., Dejax J., Richir P., Véran M., Limon-Duparcmeur F., & et al (1999).  Un nouveau genre de dinosaure sauropode de la formation des Grès supérieurs (Aptien-Albien) du Laos. Comptes Rendus de l'Académie des Sciences-Series IIA-Earth and Planetary Science. 329, 609–616., Number 8 Abstract
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Moreno-Azanza, M., Balauz B., Ezquerro L., Coimbra R., Mateus O., & Nuñez-Lahuerta C. (2022).  Unbroken dinosaur eggs accumulated together do not guarantee autochthony of the fossil assemblage. Journal of Taphonomy. 16(1-4), 129-130. Abstractmoreno-azanza_et_al_2020_unbroken_eggs.pdf

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Rotatori, F. M., Ferrari L., Sequero C., Camilo B., Mateus O., & Moreno-Azanza M. (2024).  An unexpected early-diverging iguanodontian dinosaur (Ornithischia, Ornithopoda) from the Upper Jurassic of Portugal. Journal of Vertebrate Paleontology. e2310066.: Taylor & Francis AbstractWebsite

Iguanodontia is a diverse clade of herbivorous ornithischian dinosaurs that were speciose and abundant during the Jurassic and Cretaceous. Although the monophyly of Iguanodontia is well supported, their internal relationships have sparked heated debate due to several phylogenetic paradigm shifts. Late Jurassic basally branching iguanodontians in particular are not well understood in terms of their systematic affinities and evolutionary relevance. Their fossil record in Europe is meager compared with North America, with only a few species currently recognized. Two taxa are currently known from the Upper Jurassic of England, the basally branching styracosternan Cumnoria prestwichii and the putative dryosaurid Callovosaurus leedsi. In the Upper Jurassic of Portugal, the styracosternan Draconyx loureiroi and the dryosaurid Eousdryosaurus nanohallucis are presently the only described basally branching iguanodontians. Here we report a new species of early diverging iguanodontian from the Upper Jurassic Lourinhã Formation of western-central Portugal. The new species is clearly distinguished from all other coeval taxa by an exclusive combination of characters that include a tibia with a cnemial crest that is directed craniolaterally and a fibular condyle that is angled at 90° with respect to the proximal epiphysis, a fibula with symmetrical proximal margins, and a reduced metatarsal I. The phylogenetic relationships of the Lourinhã iguanodontian were explored using maximum parsimony and Bayesian inference. The two analyses recover the Lourinhã iguanodontian as an indeterminate dryomorphan, with more precise affinities precluded due to the current available material. Body size is estimated between 3 and 4 meters for the holotype specimen, adding to the diversity of small ornithopods already recognized in the paleoichnological record of the Lourinhã Formation. http://zoobank.org/urn:lsid:zoobank.org:pub:5F4D52D0-0F0B-4809-8561-BE58C7C97D45

Mateus, O. (1999).  Upper Jurassic dinosaurs of Lourinhã (Portugal). Journal of Vertebrate Paleontology. 19(Suppl. to 3), 62A., Number (Suppl. to 3)mateus_1999_upper_jurassic_lourinha_portugal_svp_1999_abstracts.pdfWebsite
Mateus, I., Mateus H., Antunes M. T., Mateus O., Taquet P., Ribeiro V., & Manuppella G. (1998).  Upper Jurassic Theropod Dinosaur embryos from Lourinhã (Portugal). Mem. Acad. Ciências de Lisboa. 37, 101-109. Abstractmateus_et_al_1998_-_upper_jurassic_theropod_dinosaur_embryos_from_lourinha_portugal_-_upper_jurassic_palaeoenvironments_in_portugal_ed._....pdfWebsite

Upper Jurassic nesting site from Paimogo (Lourinhã, Portugal) yielded the oldest dinosaur theropod embryos ever found. Numerous bones, including skull bones, from the skeleton of these embryos have been collected. The study of bones and embryos offers the possibility to learn more on the early life of theropod dinosaurs.

Mateus, I., Mateus H., Antunes M. T., Mateus O., Taquet P., Ribeiro V., & Manuppella G. (1998).  Upper Jurassic Theropod Dinosaur embryos from Lourinhã (Portugal). Upper Jurassic paleoenvironments in Portugal, Mem. Acad. Ciências de Lisboa. 37, 101-109. Abstract
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Mateus, O., Dinis J., & Cunha P. (2014).  Upper Jurassic to Lowermost Cretaceous of the Lusitanian Basin, Portugal-landscapes where dinosaurs walked. Ciências da Terra, special. , Number 8 Abstract
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Guillaume, A. R. D., Ezquerro L., Moreno-Azanza M., & Mateus O. (2023).  Vertebrate microfossil assemblages from the Lourinhã Formation: a sneak peek on the paleoecology of the Late Jurassic in Portugal. The Anatomical Record. 306(#S1), 118-121.: Conference: 14th Symposium on Mesozoic Terrestrial Ecosystems and BiotaAt … Abstractguillaume_et_al_2023_vertebrate_microfossil.pdf

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Clemmensen, L. B., Milàn J., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2015).  The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data. Geological Society, London, Special Publications. 434(1), 31-47. Abstractclemmensenetal2015greenland.pdfWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

Clemmensen, L. B., Milàn J., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2015).  The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data. Geological Society, London, Special Publications. 434, AbstractWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

Jackson, Y., Economos R., Jacobs L., Mateus O., & Gonçalves A. O. (2021).  When Dinosaurs Walked Through Diamonds: Constraining the Age of Early Cretaceous Footprints in Volcanic Crater Sediments. SMU Journal of Undergraduate Research. 6(1), : DOI: https://doi.org/ 10.25172/jour.6.1.1 Available at: https://scholar.smu … Abstractwhen_dinosaurs_walked_through_diamonds.pdf

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Ripple, W. J., Wolf C., Newsome T. M., Galetti M., Alamgir M., Crist E., Mahmoud M. I., Laurance W. F., & other scientist signatories +15 364 (2017).  World Scientists’ Warning to Humanity: A Second Notice. BioScience. bix125. Abstractripple_et_al_2017_scientists_merged_with_supp_material.pdfWebsite

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Ripple, W. J., Wolf C., Newsome T. M., Galetti M., Alamgir M., Crist E., Mahmoud M. I., Laurance W. F., & signatoriesscientist +15364 (2017).  World Scientists’ Warning to Humanity: A Second Notice. BioScience. 125, Abstract
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Mateus, O., Mannion P. D., & Upchurch P. (2014).  Zby atlanticus, a new turiasaurian sauropod (Dinosauria, Eusauropoda) from the Late Jurassic of Portugal. Journal of Vertebrate Paleontology. 34(3), 618-634. Abstractmateus_et_al_2014_zby_atlanticus.pdfWebsite

Here we describe a new partial sauropod skeleton from the late Kimmeridgian (Late Jurassic) of the Lourinhã Formation, central west Portugal. The closely associated specimen comprises a complete tooth (with root), a fragment of cervical neural arch, an anterior chevron, and an almost complete right pectoral girdle and forelimb. The new sauropod, Zby atlanticus, n. gen. et sp., can be diagnosed on the basis of four autapomorphies, including a prominent posteriorly projecting ridge on the humerus at the level of the deltopectoral crest. Nearly all anatomical features indicate that Zby is a non-neosauropod eusauropod. On the basis of several characters, including tooth morphology, extreme anteroposterior compression of the proximal end of the radius, and strong beveling of the lateral half of the distal end of the radius, Zby appears to be closely related to Turiasaurus riodevensis from approximately contemporaneous deposits in eastern Spain. However, these two genera can be distinguished from each other by a number of features pertaining to the forelimb. Whereas previously described Late Jurassic Portuguese sauropods show close relationships with taxa from the contemporaneous Morrison Formation of North America, it appears that turiasaurians were restricted to Europe. All adult sauropods recovered in the Late Jurassic of Portugal thus far are very large individuals: it is possible that the apparent absence of small- or medium-sized adult sauropods might be related to the occupation of lower-browsing niches by non-sauropods such as the long-necked stegosaur Miragaia longicollum.

Mateus, O., Mannion P. D., & Upchurch P. (2014).  Zby atlanticus, a new turiasaurian sauropod (Dinosauria, Eusauropoda) from the Late Jurassic of Portugal. Journal of Vertebrate Paleontology. 34, 618-634., Number 3 Abstract
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Mateus, O., Mannion P. D., & Upchurch P. (2014).  Zby atlanticus, a new turiasaurian sauropod (Dinosauria, Eusauropoda) from the Late Jurassic of Portugal. Journal of Vertebrate Paleontology. 34, 618–634., Number 3 Abstract
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Martins, R. M. S., Castanhinha R. A., Mateus O., Araújo R., Beckmann F., & Schell N. (2012).  {Synchrotron radiation-based techniques applied to the study of dinosaur fossils from the collection of the museum of Lourinhã. Ciencia e Tecnologia dos Materiais. 24, 153-156., Number 3-4 Abstract
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Milan, J., & Mateus O. (2005).   Jagten på Europas største dinosaur. Naturens Verden. 88(10), 2-13. Abstract
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Magazine Article
Miscellaneous
Mateus, O. (2013).  Cabinda revisited: age and environment of new Cenozoic vertebrate fossils from northern Angola. 45, , 1 Abstract

In the early 20thcentury, Belgian naturalists reported Paleocene and Eocene sharks, the bothremydid pleurodiran turtleTaphosphrys(formerlyBantuchelys), and a neosuchian and the dyrosaurid crocodyliformCongosaurusfrom coastal outcrops near Landana in the northern province of Cabinda, Angola. In 1935, rare and fragmentary mammals were reported from strata at Malembo Point, south of Landana, and originally considered to be Miocene in age. Subsequent re-identification of the mammal fossils suggested that the Malembo deposits are Lower Oligocene based on the presence of an arsinoithere and hyracoids. An anthropoid canine, originally identified as a carnivore incisor, was also recognized. In four recent expeditions to Cabinda, Projecto PaleoAngola has traced and measured the stratigraphy between Landana and Malembo Point and sampled these deposits for pollen, stable isotopes, detrital zircons, paleomagnetic stratigraphy, and for U/Pb dating of bones, teeth, and coprolites. Although the faunas from all Cabinda localities are dominated by sharks and rays, new discoveries from Landana include a complete cheloniid cryptodire turtle skull, a small snake vertebra, and a bird bone. Discoveries from the Malembo level include a narrow-snouted crocodyliform similar toCongosaurusandEuthecodon, an arsinoithere anterior tooth, an upper molar similar to that of the ptolemaiidanKelba, an unidentified mammalian incisor, and a large primate-like premolar. Recent biostratigraphic advances in East Africa and the new fossil discoveries in Cabinda suggest similarity to late Oligocene faunas in Ethiopia and Kenya, although the large primate-like premolar is unique. To this day, the fossil localities of Malembo provide the only coastal, low latitude, low elevation record of West African Cenozoic terrestrial mammals. https://gsa.confex.com/gsa/2013AM/webprogram/Paper232115.html

Brandao, J. M., Callapez P. M., Mateus O., & Castro P. (2010).  Colecções e museus de Geologia: missão e gestão. , Jan: Ed. Universidade de Coimbra e Centro de Estudos e Filosofia da História da Ciência. Abstract

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Mateus, O. (2014).  Cracking dinosaur endothermy: paleophysiology unscrambled. NA, , 1 Abstract

The amniote eggshell functions as a respiratory structure adapted for the optimal transmission of respiratory gasses to and from the embryo according to its physiological requirements. Therefore amniotes with higher oxygen requirements, such as those that sustain higher metabolic rates, can be expected to have eggshells that can maintain a greater gas flux to and from the egg. Studies of extant amniotes have found that eggshells of reduced porosity impose a limit on the metabolic rate of the offspring. Here we show a highly significant relationship between metabolic rates and eggshell porosity in extant amniotes that predicts highly endothermic metabolic rates in dinosaurs. This study finds the eggshell porosity of extant endotherms to be significantly higher than that of extant ectotherms. Eggshell porosity values of dinosaurs are found to be significantly higherthan that of extant ectotherms, but not extant endotherms. Dinosaur eggshells are commonly preserved in the fossil record, and porosity may be readily identified and measured. This provides a simple tool to identify metabolic rates in extinct egg-laying tetrapods whose eggs possessed a mineralized shell

Mateus, O. (2009).  The Cretaceous Skeleton Coast of Angola. 29, , 1 Abstract
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Mateus, O. (2013).  Decapod crustacean body and ichnofossils from the Mesozoic of Portugal. NA, , 1 Abstract

Book of abstracts of the 5th Symposium on Mesozoic and Decapod Crustaceans

Mateus, O. (2011).  A new metoposaurid (temnospondyl) bonebed from the Late Triassic of Portugal. 31, , 1 Abstract

The end-Triassic extinction event (ETE), considered one of the ‘Big Five’ mass extinctions, marks a dividing line between early Mesozoic vertebrate assemblages, typically including abundant temnospondyls, basal synapsids and basal archosaurs, and ‘typical’ Mesozoic faunas dominated by dinosaurs, pterosaurs, crocodylomorphs, turtles and mammaliaforms. Recent geochemical work has provided strong evidence that the ETE is synchronous with, and likely caused by, the emplacement of the Central Atlantic magmatic province (CAMP). However, stratigraphic sections containing both terrestrial vertebrates and CAMP basalts are scarce, complicating attempts to examine terrestrial faunal changes during this extinction event. The Triassic–Jurassic Algarve Basin, southern Portugal, is an extensional rift basin to-marginal marine red beds (the ‘Grés de Silves’ Group) interbedded with CAMP basalts.... bonebed from the interval ‘AB1’ of the Grés de Silves. Preliminary excavations yielded at least nine well-preserved temnospondyl individuals represented by partial to nearly complete skulls and disarticulated postcranial elements of juvenile to adult ages. Nearly all material appears to represent a single species of metoposaurid referable to the genus Metoposaurus, well known from the late Carnian–early Norian of Germany and Poland. A number of char- acters of the occiput and mandible suggest that the Algarve material may represent a new species. This new material provides new data on the diversity and paleogeographical distri- bution of the metoposaurids, a highly autapomorphic and peculiar group composed of large aquatic carnivores with a unique elongated but brevirostral skull. This taxon also provides [...] Horizon may be within or close to the late Carnian–early Norian. Additional bone-bearing horizons within the ‘Grés de Silves’ provide a rare opportunity to examine terrestrial faunal change in the lead-up to the ETE.

Mateus, O. (2010).  Physical drivers of evolution and the history of the marine tetrapod fauna of Angola. –, , 1 Abstract

Modern marine species populations are often evaluated in terms of bottom-up, resource limited structure, or top-down, predator controlled structure. In a larger timeframe, investiga- tion of physical drivers in marine tetrapod evolution relies on the recognition of patterns and the correlation in timing of physical events with biotic change. However, it has been dem- onstrated through the study of fossil cetaceans that a broader deep-time perspective within a top-down or bottom-up framework is informative. Here we examine the fossil record of &UHWDFHRXV PDULQH WHWUDSRGV LQ $QJROD WR GLVFHUQ SDWWHUQV WKDW PD\ UHÀHFW SK\VLFDO GULYHUV RI evolution, and that are also relevant to population structure. In modern marine ecosystems, GLVWULEXWLRQ SDWWHUQV UHÀHFWLQJ SULPDU\ SURGXFWLYLW\ DUH LQGLFDWLYH RI ERWWRP?XS FRQWURO? ,Q the fossil record, productivity-controlled distribution patterns can also be perceived. Physi- cal parameters resulting in environmental stability, sea-level change, oceanic anoxic events, paleoclimate, and paleogeography are examined in comparison with taxonomic diversity and life history patterns. Mosasaurs originated during a time of high global temperatures and shallow temperature gradients. As upper-trophic-level species of modest size and plesiopedal limb structure (capable of terrestrial locomotion), early mosasaurs were subject to both top- down and bottom up pressures. The attainment of larger size coupled with emigration and biogeographic distribution in areas of high primary productivity, and niche differentiation VKRZQ E\ 13C values, indicate bottom-up pressures. Productivity along the African coast since the formation of the Atlantic Ocean facilitated the co-occurrence of diverse marine tetrapods through time, and has culminated today in the Benguela large marine ecosystem. Just as the current Benguela ecosystem has tetrapod species populations dominated by both bottom-up (cetaceans) and top-down strategies (sea birds and pinnipeds), so too did the Cre- taceous community, with mosasaurs and plesiosaurs having predominantly bottom-up popu- lation structure, while sea turtles and pterosaurs were more subject to top-down pressures.

Thesis