The fine line between complexity and inaccuracy

Trait-dependent diversification models can be enticing in that a simple setup can give fascinating results. However, without thoughtful model design, conclusions drawn from the models may be wrong. Model design is a balancing act between increasing model complexity to accurately portray a complex reality without increasing it so much that results are inaccurate. While weContinue reading “The fine line between complexity and inaccuracy”

Vertical stratification of ant assemblages in Brazilian savanna

Tropical terrestrial habitats are renowned for their exceptional biodiversity, and one contributing factor is vertical stratification.  Differences in abiotic and biotic conditions from the ground to the top of trees favour the occurrence of distinct species assemblages on the ground and on trees. Our study shows that the degree of this distinction increases with increasingContinue reading “Vertical stratification of ant assemblages in Brazilian savanna”

Tracing plant dispersal into the Pacific

Of fruits, seeds, and vectors – biogeographic processes and the impact of long-distance dispersal. Above: Fruits and flowers of Epicharis cuneata (Hiern) Harms, which is a rainforest tree species from the Meliaceae. Photo credit: Alexandra N. Muellner-Riehl. This study started with the aim to investigate the biogeographic history of Dysoxylum s.l., a polyphyletic group ofContinue reading “Tracing plant dispersal into the Pacific”

Do bats follow the ‘island rule’?

The search for a yardstick to gauge geographic variation in a taxonomic context yielded answers to broader biogeographical questions Above: Geographic variants in the Allen’s common moustached (Pteronotus fuscus). Left, cranium and mandible of a specimen from Paraguaná Peninsula (CVULA 8197). Center, cranium and mandible of a specimen from Venezuela south of the Orinoco RiverContinue reading “Do bats follow the ‘island rule’?”

A glimpse into the past: complementary evidence for deciphering the history of an emblematic tree species

Long-term demographic processes of species leave behind traces in various forms, such as spatial genetic structure in extant populations and fossil remains in the ground. Combining these complementary sources of evidence from a dense sampling across the entire natural range of Swiss stone pine helped us to unravel the glacial history of this timberline species.Continue reading “A glimpse into the past: complementary evidence for deciphering the history of an emblematic tree species”

Why species are common or rare depends on spatial scale

A species that is locally common can be globally rare and vice versa. But why? Turns out that tolerance of climatic conditions drives plant species commonness towards global spatial scales, while at finer local scales, competitive ability is relatively more decisive. Accounting for this scale dependence in species occupancy is important when anticipating the effectsContinue reading “Why species are common or rare depends on spatial scale”

A Tale of Two Types of Landscape Heterogeneity

The geographic ranges of mammals in Africa are limited in size by the variation in habitats across space (habitat heterogeneity), but surprisingly not by the variation in elevations (topographic heterogeneity). Mammalian ranges will be sensitive to future habitat destruction and alteration, as climate change and human impacts continue to intensify. Above: The cheetah (Acinonyx jubatus)Continue reading “A Tale of Two Types of Landscape Heterogeneity”

Plant reproductive mode: inherited or influenced by environments?

Plants can reproduce clonally or by seeds. What are the circumstances that clonal reproduction is favoured, and which type of species are most likely to be clonal? Above: Plants reproduce asexually via rhizomes. Sexual reproduction from seeds is common in the plant kingdom. However, many plants reproduce through vegetative propagation or clonal growth such asContinue reading “Plant reproductive mode: inherited or influenced by environments?”

Island theory is still relevant to alpine biogeography

Area, environmental heterogeneity, scale and the conservation of alpine diversity. Above: Phyteuma hemisphericum from the Sierra de Villabandín, Cantabrian Mountains, Spain; photograph by Borja Jiménez-Alfaro This project was an extension of our work on the relative importance of geographic distance and environmental difference to the beta diversity of alpine plant communities (Malanson et al. 2022).Continue reading “Island theory is still relevant to alpine biogeography”

Elucidating river history through population genetics of an aquatic organism

Rivers sometimes change their way, caused by geological events. During such river rearrangement, what happened to the inhabitants? We investigated the genetic traces remaining in genomes of the descendants and look for a way to find unidentified geological events. Above: An upper reach of mountain stream on Honshu Island, Japan. Honshu Island, the main islandContinue reading “Elucidating river history through population genetics of an aquatic organism”