The Vallesian, 11.1-9 Ma, was a special time in the Vallès-Penedes basin near Barcelona, where a biodiversity hotspot existed. Europe had a subtropical climate, with rhinos, forest giraffes, lions,... Show moreThe Vallesian, 11.1-9 Ma, was a special time in the Vallès-Penedes basin near Barcelona, where a biodiversity hotspot existed. Europe had a subtropical climate, with rhinos, forest giraffes, lions, hyenas, flying squirrels and primates.Around 9.7 million years ago there was an abrupt collapse in diversity; the so-called 'Vallesian Crisis'. This was seen as the transition point to a climate with more seasonality and open landscapes.Using a fossil dataset from Miocene Eurasia, the influence of dataset quality on the severity of this crisis, which animals were most affected and their distribution patterns was studied.The crisis’ victims have three things in common: they are mainly forest dwellers, they date back to the Middle Miocene (16-11.1 Ma), and they are rare during the early Vallesian. The high Vallesian biodiversity was caused by the arrival of new immigrants in addition to older transient groups, possibly due to the unique coastal conditions.Major differences existed between the coastal region and the interior of the Iberian Peninsula. Some species appeared in the Vallès-Penedès, but never reached the inland. The 'Vallesian Crisis', while seen understandably as a time of abrupt and severe extinction, was thus largely a local turnover event. Show less
The largest genus within the Phyllanthaceae family is a group called Phyllanthus L. Recent studies have shown, that Phyllanthus is paraphyletic with the genera Glochidion, Breynia and Synostemon... Show moreThe largest genus within the Phyllanthaceae family is a group called Phyllanthus L. Recent studies have shown, that Phyllanthus is paraphyletic with the genera Glochidion, Breynia and Synostemon nested within it. In this thesis, I study the evolution and systematics of Phyllanthus and how to solve the apparent paraphyly. First we explore past morphological subgroups to come to a subdivision, which was tested using molecular phylogenetics. Several species of Phyllanthus are also used in traditional medicine and by utilizing the living collections of the Hortus botanicus Leiden, we tested for antibacterial and antifungal bioactivity. The phylogeny resulting from this study is used to study the historical biogeography and diversification of the tribe and to propose a new classification where Phyllanthus is separated into several smaller genera. Show less
Fagernäs Z.; Salazar-García, D.C.; Haber Uriarte, M.; Avilés Fernández, A.; Henry A.G.; Lomba Maurandi, J.; ... ; Warinner, C. 2022
The oral cavity is a heterogeneous environment, varying in factors such as pH, oxygen levels, and salivary flow. These factors affect the microbial community composition and distribution of species... Show moreThe oral cavity is a heterogeneous environment, varying in factors such as pH, oxygen levels, and salivary flow. These factors affect the microbial community composition and distribution of species in dental plaque, but it is not known how well these patterns are reflected in archaeological dental calculus. In most archaeological studies, a single sample of dental calculus is studied per individual and is assumed to represent the entire oral cavity. However, it is not known if this sampling strategy introduces biases into studies of the ancient oral microbiome. Here, we present the results of a shotgun metagenomic study of a dense sampling of dental calculus from four Chalcolithic individuals from the southeast Iberian peninsula (ca. 4500–5000 BP). Interindividual differences in microbial composition are found to be much larger than intraindividual differences, indicating that a single sample can indeed represent an individual in most cases. However, there are minor spatial patterns in species distribution within the oral cavity that should be taken into account when designing a study or interpreting results. Finally, we show that plant DNA identified in the samples is likely of postmortem origin, demonstrating the importance of including environmental controls or additional lines of biomolecular evidence in dietary interpretations. Show less
Dissochaeta Blume (Melastomataceae, tribe Dissochaeteae) is well-known as a scrambling plant genus found in Southeast Asia, where it is an inhabitant of the tropical rainforests or evergreen... Show moreDissochaeta Blume (Melastomataceae, tribe Dissochaeteae) is well-known as a scrambling plant genus found in Southeast Asia, where it is an inhabitant of the tropical rainforests or evergreen forests.The main objectives of this thesis are to clarify the relationships among species and genera within the Dissochaeta alliance and to provide a new classification, which reflects the evolutionary and biogeographic traits of this plant group. The study focuses on three aspects of the Dissochaetaalliance: the taxonomy, molecular phylogeny and historical biogeography. Show less
This thesis reviews the available coral studies in the Persian Gulf at a large scale, discusses the environmental challenges for corals in the context of climate change, and expands our... Show more This thesis reviews the available coral studies in the Persian Gulf at a large scale, discusses the environmental challenges for corals in the context of climate change, and expands our knowledge of coral biodiversity and biogeography of the region, highlights the remaining gaps in our knowledge and goes on to provide recommendations for further research. This is of special importance given recent international interest in the region as a harbinger of coral adaptation to climate change as the impacts to the global environment, human society and the economy unfold. Show less
Janssens, Steven B.; Groeninckx, Inge; De Block, Petra J.; Verstraete, Brecht; Smets, Erik F.; Dessein, Steven 2016
Gall crabs (Crustacea : Cryptochiridae) are small, coral-dwelling crabs that live in obligate association with their host corals (Scleractinia), on which they rely for food and shelter. They have... Show moreGall crabs (Crustacea : Cryptochiridae) are small, coral-dwelling crabs that live in obligate association with their host corals (Scleractinia), on which they rely for food and shelter. They have been recorded from shallow and deeper waters (over 500 m), but the majority of the species live in reef corals in the photic zone. The highest number of species is recorded from the Indo-West Pacific, where coral diversity is highest. This PhD thesis deals with various aspects of their evolution and diversification; four species are described as new to science, and the host specificity, biogeography, distribution and reproductive morphology of gall crabs are studied. In addition, the close association between gall crabs and corals allowed for studies on (cryptic) speciation and possible coevolution. Results show that the observed coevolutionary events should most probably be ascribed to sequential evolution, which indicates that the phylogeny of the gall crabs has been directed by the evolution of the corals. Show less
Five research methods were used in Taxonomy, Systematics, and Biogeography of Ficus subsection Urostigma(Moraceae); Morphological characters, leaf anatomy, pollen morphology, molecular phylogeny,... Show moreFive research methods were used in Taxonomy, Systematics, and Biogeography of Ficus subsection Urostigma(Moraceae); Morphological characters, leaf anatomy, pollen morphology, molecular phylogeny, and historical biogeography. Seven topics are the result: 1) A revision was made based on morphology in which 27 species are recognized, but which also showed that morphology alone cannot solve all problems because of variation within the species. 2) Leaf anatomy displayed less variation in characters and anatomical characters proved to be useful for the classification of Ficus, especially in combination with morphology. 3) Pollen morphology appeared to be similar for all species and the characters can merely be used for generic recognition. 4) A new classification for subsection Urostigma is proposed in which the circumscription of the subsection and the species is the result of combining molecular phylogenetic information with morphology and leaf anatomy. 5) Ficus cornelisiana, a new species from Sino-Himalayan, was reported based on morphological and leaf anatomical evidence. 6) The historical biogeography was studied by using molecular dating and ancestral area reconstruction. 7) The use of some Thai species within subsect. Urostigma is reported, six of them are used as food, as ornamental, or the uses are related to religion or sacred purposes. Show less
Derris Lour. (family Fabaceae/tribe Millettieae) is a quite well-known legume genus as many species are a source of Rotenone toxin, a commercial organic insecticide and fish poison used in many... Show moreDerris Lour. (family Fabaceae/tribe Millettieae) is a quite well-known legume genus as many species are a source of Rotenone toxin, a commercial organic insecticide and fish poison used in many countries. The genus is characterized mainly by its indehiscent, flat, thin but leathery pods with usually wing(s) along the suture(s). In the tribe Millettieae, however, there are several plants in the tropical areas of the old and new world which have similar pods and other morphological characters comparable to Derris. They all are called Derris-like taxa (or Derris-like plants) in this thesis. In the course of time, different generic circumscriptions of these plants were proposed by various taxonomists. The main objectives of this thesis are to clarify the relationships between species and genera within this complex group of Derris-like taxa [mainly focused on the old-world Asian genera: Aganope, Brachypterum and Derris (+Paraderris)] and to provide a new classification which reflects the evolutionary and biogeographic relationships of these plants. Show less
Hoverflies of the subfamily Microdontinae (Diptera: Syrphidae) have a reputation for causing confusion. Their diversity in shape and size is astonishing: from large, furry-haired species and... Show moreHoverflies of the subfamily Microdontinae (Diptera: Syrphidae) have a reputation for causing confusion. Their diversity in shape and size is astonishing: from large, furry-haired species and convincing wasp-mimics to tiny, unsightly creatures, easily mistaken for something uninteresting. The larvae resemble slugs so much that biologists have described them as molluscs on several occasions. Worldwide, hundreds of species of Microdontinae have been described, but so far there has been no comprehensive attempt to unravel this hotchpotch of names. This thesis examines the phylogenetic relationships of Microdontinae, based on morphological and molecular characters, in order to construct a new classification of the subfamily. A total number of 51 (sub)genera (11 new) are recognized, in which 472 valid species (49 new) are classified, resulting in many new combinations. The newly proposed classification facilitates species level taxonomy. In addition, it should provide a framework for further research on biogeography, (cryptic) speciation and evolution of host specialization. This thesis takes a first shot at some of these subjects by exploring the taxonomy of Neotropical Microdontinae that mimic stingless bees, reviewing and evaluating the associations of these flies with ants, and speculating on their historical biogeography. Show less
The text mainly deals with the Eurasian evolutionary history of mammoths. It focuses on the time bracket 1.0-0.6 Ma, within which Mammuthus meridionalis (the southern mammoth) finally became... Show moreThe text mainly deals with the Eurasian evolutionary history of mammoths. It focuses on the time bracket 1.0-0.6 Ma, within which Mammuthus meridionalis (the southern mammoth) finally became extinct in Europe. Its descendant,the initially eastern Asian steppe mammoth (M. trogontherii) was a comparatively late immigrant in Europe (c. 1.2-1.0 Ma)and then for a time was the only mammoth species there. European sites that yielded relevant material are rivised. The probability of hybridisation between the said species, suggested by the occurrence of so-called mosaic molars, is discussed. In addition, a number of subspecific taxa traditionally referred to M. meridionalis is now ascribed to M. trogontherii, which reduces the role played by M. meridionalis at the end of the Early Pleistocene. Show less
This thesis presents a detailed molecular phylogenetic and biogeographic study of the Spathelioideae clade, a group of seven small Sapindalean genera with remarkable morphological diversity. The... Show moreThis thesis presents a detailed molecular phylogenetic and biogeographic study of the Spathelioideae clade, a group of seven small Sapindalean genera with remarkable morphological diversity. The systematic placement of these genera has always been in dispute and the results of this thesis show that Spathelioideae are a monophyletic sister clade to the Rutaceae family. Except for the South American and Caribbean genus Spathelia, all Spathelioideae genera are monophyletic. The South American species have been transferred to a resurrected genus Sohnreyia accordingly. Molecular dating analyses suggest an origin of Spathelioideae in the Late Cretaceous. Assuming a palaeotropic origin of Rutaceae, the stem lineage of Spathelioideae might have originated in Central western and central Africa. The divergence of a Neotropical and a Palaeotropical lineage of Spathelioideae might be explained by long-distance dispersal during the Late Cretaceous or Palaeocene. Within the Neotropical clade, one dispersal event to the Caribbean occurred possibly via a landbridge or a series of islands. Sea level changes in the Pleistocene have isolated and connected landmasses in the Caribbean and might have been triggers for speciation of the genus Spathelia. Within the Palaeotropic clade, dispersal events from Africa to the Mediterranean & Canary Islands, Madagascar, and South-East Asia occurred. Show less
Forest damselflies (family Platystictidae) are widespread in southeast Asia from Sri Lanka to New Guinea, and are also known from Central America and the northern part of South America. The larvae... Show moreForest damselflies (family Platystictidae) are widespread in southeast Asia from Sri Lanka to New Guinea, and are also known from Central America and the northern part of South America. The larvae of most species live in small streams or seepages under forest canopy. Adults are found hanging from the tips of leaves or twigs along streams. The family is thought to have evolved more than 100 million years ago. Only 213 species are known worldwide, of which the author described 46 as new to science. Although most species are remarkably similar in general appearance, they show significant variation in structural details such as wing venation, pronotum, and secondary genitalia of the male. The group is ideal for biogeographical studies, since most species have small distributional ranges. A reconstruction of the phylogeny shows that several ancient lineages occur along the margin of the Indian Plate. Although Platystictidae are not known from Africa, it is hypothesized that the family evolved on that continent. The ancestors of the subfamilies Platystictinae and Sinostictinae drifted with India to Asia between 100 and 45 Ma. A scenario of the historical biogeography of the Platystictinae is described in relation to the palaeogeography of southeast Asia since the Eocene. The subfamily Palaemnematinae most likely dispersed from Africa to the New World via Europe and the ‘North Atlantic Land Bridge’. Show less
Based on the digitized herbarium records housed at the National Herbarium of the Netherlands I developed high spatial resolution patterns of Borneo's botanical richness, endemicity, and the... Show moreBased on the digitized herbarium records housed at the National Herbarium of the Netherlands I developed high spatial resolution patterns of Borneo's botanical richness, endemicity, and the floristic regions. The patterns are derived from species distribution models which predict a species occurrence based on the identified relationships between species recorded presences and the ecological circumstances at those localities. A new statistical method was developed to test the species distribution models. Several areas of high richness and endemicity were added to the list of previous known ones. Furthermore, the lowland rain forest of Borneo, previously recognized as one floristic region, in fact harbours at least four (and possibly six) different floristic regions. Show less
The snails__ proverbial inertness makes it an ideal subject to study the patterns and processes that lead to speciation. The land snail family Chondrinidae consists of about 70 extant species in... Show moreThe snails__ proverbial inertness makes it an ideal subject to study the patterns and processes that lead to speciation. The land snail family Chondrinidae consists of about 70 extant species in six genera. They occur throughout western and central Europe, northern Africa and as far east as Pakistan. These snails share a long and interesting evolutionary history, to the knowledge of which we contribute here. Show less
Africa has a large and almost uninterrupted land surface that is isolated from surrounding continents. In the last 20 million years Africa had a variable and increasingly dry climate. As a result... Show moreAfrica has a large and almost uninterrupted land surface that is isolated from surrounding continents. In the last 20 million years Africa had a variable and increasingly dry climate. As a result the Afrotropics have only half as many odonate species as tropical America or Asia. __Relict__ families are scarce and concentrated in five isolated, climatically stable areas: (1) the Cameroon highlands, (2) locally in East Africa, (3) the Cape region, (4) the granitic Seychelles, and especially (5) Madagascar. Most African odonate species, about two-fifths, are restricted to the Central and West African forests. The remainder is found, in three fairly equal parts, in (1) the highlands from Arabia to the Cape, (2) Madagascar and surrounding archipelagos, and (3) open habitats throughout the region. Most mainland species appear related to the relatively diverse fauna of tropical Asia, but have few relatives on Madagascar, suggesting that the modern continental fauna mostly diversified after the arrival of Asian ancestors. Being best adapted to change, Coenagrionidae and Libellulidae are the largest odonate families on Earth. Only in temperate regions, impacted strongly by the ice ages, is their dominance comparable to that in changeable Africa. The climatic influence is further seen in forest species __stranded__ in highlands by forest reduction, savanna species __trapped__ by forest expansion, and overseas colonisation of East Africa by island species. Traditional theory is that speciation took place in habitat fragments created by climatic change, especially in forest refuges, but such refuges seem to conserve old species rather than generate new ones. Abrupt habitat gradients in heterogeneous landscapes may be more important in speciation, especially close to areas where potential ancestors are conserved. The habitat mosaic on the Congo-Zambezi watershed is the best modern example of such an area. Phylogenetic research of various African plants and animals indicate that environmental and dispersal barriers are easily straddled, with savanna species radiating from a forest ancestors and vice versa. Species were eliminated with climatic change, but new ecological space was also constantly created. Such processes must also have lead to the __demise__ of most of Africa__s old odonate diversity and the __rise__ of a rich new fauna. Show less
The thesis describes the design and evolution of echolocation in the South and Southeast Asian Swiftlets. It starts explaining the molecular phylogenetics of Swiftlets, which is used in subsequent... Show moreThe thesis describes the design and evolution of echolocation in the South and Southeast Asian Swiftlets. It starts explaining the molecular phylogenetics of Swiftlets, which is used in subsequent chapters. Echolocation calls and social vocalisations of Swifts are compared between species and with non-echolocating Swifts and Swiftlets. The following chapters treat potential morphological adaptations in the echolocation system, i.e. in the syrinx, ear, and brain. The final chapters discuss the biogeography of the Swiftlets and integrate the results into an overall hypothesis on the evolution of Swiftlets and their echolocation system. Show less
