Greg Lamarre

• PhD
• Researcher at Czech Academy of Sciences, Biology Centre

Interactions between plants, insect herbivores and associated predators represent the majority of terrestrial biodiversity. Insects are vital food sources for many other organisms and provide important ecosystem functions and services including pollination, waste removal and biological control. We propose a complete and reproducible education progr...

Insects make up the bulk of terrestrial diversity (1). Reports of insect declines, best documented in Europe and North America, suggest that 40% of insect species in temperate countries may face extinction over the next few decades (2), although this figure is probably inflated (3). Other studies have highlighted falling insect biomass in Germany a...

Research has repeatedly shown that ongoing habitat loss and the increasing frequency of extreme climatic events have altered fundamental biological processes, threatening biodiversity and ecosystem functioning worldwide. However, the multitude of interacting factors underlying the impacts of these threats remain poorly understood in tropical forest...

Understanding the causes and consequences of insect declines has become an important goal in ecology, particularly in the tropics, where most terrestrial diversity exists. Over the past 12 years, the ForestGEO Arthropod Initiative has systematically monitored multiple insect groups on Barro Colorado Island (BCI), Panama, providing baseline data for...

The Millennium Ecosystem Assessment assessed ecosystem change, human wellbeing and scientific evidence for sustainable use of biological systems. Despite intergovernmental acknowledgement of the problem, global ecological decline has continued, including declines in insect biodiversity, which has received much media attention in recent years. Sever...

Cryptic species represent significant entities in conservation planning and are common among tropical insects. Many studies focusing on cryptic species have been restricted to a narrow taxon and it is not clear whether some insect clades or assemblages may have a greater propensity for cryptic speciation than others. Here, we contrast cryptic diver...

Recent reports of insect decline have raised concerns regarding population responses of ecologically important groups, such as insect pollinators. Additionally, how population trends vary across pollinator taxonomic groups and degree of specialization is unclear. Here, we analyse 14 years of abundance data (2009–2022) for 38 species of native insec...

Insect herbivores and their parasitoids play a crucial role in terrestrial trophic interactions in tropical forests. These interactions occur across the entire vertical gradient of the forest. This study compares how caterpillar communities, and their parasitism rates, vary across vertical strata and between caterpillar defensive strategies in a se...

Although studies of insect decline have recently dominated headlines worldwide, their interpretation requires caution since for most species, we lack long‐term population baselines. In the tropics, where most insect species thrive, our knowledge is even more limited and so reliable insect assessments must originate from well‐established long‐term m...

Climate change poses a severe threat to many taxa, with increased mean temperatures and frequency of extreme weather events predicted. Insects can respond to high temperatures using behaviour, such as angling their wings away from the sun or seeking cool local microclimates to thermoregulate or through physiological tolerance. In a butterfly commun...

Climate change is a major threat to species worldwide, yet it remains uncertain whether tropical or temperate species are more vulnerable to changing temperatures. To further our understanding of this, we used a standardised field protocol to (1) study the buffering ability (ability to regulate body temperature relative to surrounding air temperatu...

The magnitude of worldwide insect decline is hotly debated, with multiple examples of stable or increasing insect populations. In addition, time series data for tropical insects are scarce, notably in rainforests where insect diversity is poorly known but reaches a peak. Despite social insects (ants, termites, bees and allies) being key organisms i...

Climate warming is considered to be among the most serious of anthropogenic stresses to the environment, because it not only has direct effects on biodiversity, but it also exacerbates the harmful effects of other human‐mediated threats. The associated consequences are potentially severe, particularly in terms of threats to species preservation, as...

The population dynamics of most tropical insects are unknown and long‐term monitoring programmes are urgently needed to evaluate a possible insect decline in the tropics. In this context, functional groups can be used effectively to summarise time‐series for species‐rich taxa. Neotropical dung beetles have often been catalogued into functional grou...

The soil fauna of the tropics remains one of the least known components of the biosphere. Long-term monitoring of this fauna is hampered by the lack of taxonomic expertise and funding. These obstacles may potentially be lifted with DNA metabarcoding. To validate this approach, we studied the ants, springtails and termites of 100 paired soil samples...

In the tropics, antagonistic seed predation networks may have different properties than mutualistic pollination and seed dispersal networks, but the former have been considerably less studied. We tested whether the structure of antagonistic tripartite networks composed of host plants, insects developing within seeds and fruits, and their insect par...

Understanding spatiotemporal trends on insect‐plant interaction networks is essential to unveil the ecological and evolutionary processes driving herbivore specialisation. However, community studies accounting for temporal dynamics in host‐plant specialisation of herbivorous insects are surprisingly scarce. Here, we investigated how seasonality aff...

Robust data to refute or support claims of global insect decline are currently lacking, particularly for the soil fauna in the tropics. DNA metabarcoding represents a powerful approach for rigorous spatial and temporal monitoring of the taxonomically challenging soil fauna. Here, we provide a detailed field protocol, which was successfully applied...

1. Assemblages of insect herbivores are structured by plant traits such as nutrient content, secondary metabolites, physical traits, and phenology. Many of these traits are phylogenetically conserved, implying a decrease in trait similarity with increasing phylogenetic distance of the host plant taxa. Thus, a metric of phylogenetic distances and re...

In arthropod community ecology, species richness studies tend to be prioritised over those investigating patterns of abundance. Consequently, the biotic and abiotic drivers of arboreal arthropod abundance are still relatively poorly known. In this cross‐continental study, we employ a theoretical framework in order to examine patterns of covariance...

Vertical niche partitioning might be one of the main driving forces explaining the high diversity of forest ecosystems. However, the forest's vertical dimension has received limited investigation, especially in temperate forests. Thus, our knowledge about how communities are vertically structured remains limited for temperate forest ecosystems. In...

Research on canopy arthropods has progressed from species inventories to the study of their interactions and networks, enhancing our understanding of how hyper-diverse communities are maintained. Previous studies often focused on sampling individual tree species, individual trees or their parts. We argue that such selective sampling is not ideal wh...

Methods to quantify plant‐insect interactions in tropical forests may miss many important arthropods and can be time consuming and uneven in capture efficiency. We describe the Amazonas‐trap, a new method that rapidly envelops the target plant for sampling arthropods. We evaluated the efficiency of the Amazonas‐trap by comparing it with two commonl...

Les interactions entre les plantes, les insectes herbivores et leurs prédateurs associés représentent la majeure partie de la biodiversité terrestre. Les insectes sont au cœur du monde vivant et participent, grâce à leurs nombreux rôles, au bon fonctionnement de nos écosystèmes. Nous proposons un programme d'éducation environnemental complet et rep...

We have little knowledge of the response of invertebrate assemblages to climate change in tropical ecosystems, and few studies have compiled long-term data on invertebrates from tropical rainforests. We provide an updated list of the 72 species of Saturniidae moths collected on Barro Colorado Island (BCI), Panama, during the period 1958-2016. This...

Arthropods represent most of terrestrial biodiversity and are known to perform most of the crucial ecosystem services. In tropical forest, especially, we have a very incomplete understanding of how arthropod communities are assembled taxonomically but above all functionally. Species that share similar functional attributes (but not necessarily a co...

This study focuses on the importance in hyperdiverse regions, such as the Amazonian forest, of accelerating and optimising the census of invertebrate communities. We carried out low‐intensity sampling of tropical moth (Lepidoptera) assemblages in disturbed forest fragments in Brazil. We combined DNA barcoding and taxonomists’ expertise to produce f...

READ article (in French) online https://theconversation.com/hommage-aux-insectes-source-dinspiration-et-de-nourriture-2-54842

READ article (in French) on the website https://theconversation.com/hommage-a-lhistoire-naturelle-et-surtout-aux-insectes-1-54841

In the Amazon basin and the Guiana Shield, white-sand (WS) forests are recognized as a low-resource habitat often composed by a distinct flora with many edaphic endemic plants. Small patches of nutrient-poor white-sand forests can pose a series of challenges to plants and animals. For plants, these challenges have been shown to function as strong f...

Arthropods represent most of global biodiversity, with the highest diversity found in tropical rain forests. Nevertheless, we have a very incomplete understanding of how tropical arthropod communities are assembled. We conducted a comprehensive mass sampling of arthropod communities within three major habitat types of lowland Amazonian rain forest,...

Les interactions entre les êtres vivants sont à la base du fonctionnement du monde biologique. Ces relations sont complexes et prennent de nombreuses formes comme la prédation, la compétition ou le mutualisme. L'une d'elles est le mimétisme. Celle-ci consiste, pour un organisme donné, à tirer un avantage en ressemblant à un organisme d'une autre es...

Variations in diel activity among hyperdiverse tropical communities of moths, despite representing a key component of niche partitioning between species, have barely been studied so far. Using light trapping from dawn to sunset over a 1-year period in French Guiana, we investigated these variations within and between two families of moths (Sphingid...

Hyperchiria mesonesi n. sp. (Lepidoptera: Saturniidae: Hemileucinae) is described from Amazonian Peru, and compared with H. aniris (Jordan, 1910).

Herbivory is viewed as a major driver of plant evolution and the most important energy pathway from plants to higher trophic levels. Therefore, understanding patterns of herbivory on plants remains a key focus in evolution and ecology. The evolutionary impacts of leaf herbivory include altering plant fitness, local adaptation, the evolution of defe...

Growth defense tradeoff theory predicts that plants in low-resource habitats invest more energy in defense mechanisms against natural enemies than growth, whereas plants in high-resource habitats can afford higher leaf loss rates. A less-studied defense against herbivores involves the synchrony of leaf production, which can be an effective defense...

Herbivores are often implicated in the generation of the extraordinarily diverse tropical flora. One hypothesis linking enemies to plant diversification posits that the evolution of novel defenses allows plants to escape their enemies and expand their ranges. When range expansion involves entering a new habitat type, this could accelerate defense e...

Tropical forests are predicted to harbor most of the insect diversity on earth, but few studies have been conducted to characterize insect communities in tropical forests. One major limitation is the lack of consensus on methods for insect collection. Deciding which insect trap to use is an important consideration for ecologists and entomologists,...

Tropical plant diversity is extraordinarily high at both local and regional scales. Many studies have demonstrated that natural enemies maintain local diversity via negative density dependence, but we know little about how natural enemies influence beta‐diversity across habitats and/or regions. One way herbivores could influence plant beta‐diversit...

Herbivorous insects are hypothesized to promote tropical plant diversity by exerting different pressures on plants across gradients of resource availability. Nonetheless, few studies have characterized insect communities across the broad gradient of soil fertility that occurs in the Amazon basin. Contrasting predictions can be made for insect abund...

We investigate spider communities from French Guiana tropical rainforest to discover species new to Science and also for understanding the distribution and ecology of the spider of the Guianese shield. Spiders inhabit every micro-habitats of the forest and inclusive surveys must take this large distribution into account. In order to discover new me...

Dans le cadre de nos recherches en écologie des communautés, nous avons intégré une échelle d’habitat forestier dans le but de tester si la composition et la structure des communautés végétales peuvent avoir une influence sur la densité de coléoptères de trois grands types d’habitats de la forêt tropicale de Guyane française : les forêts de terra...

Background/Question/Methods Tropical plant diversity is extraordinarily high both at local and regional scales. Increasing evidence has demonstrated the critical role of natural enemies in maintaining local diversity via negative density-dependence, but we know very little about how natural enemies influence beta-diversity across habitats and/or...