First documented record of Amazilia tzacatl (de la Llave, 1893) (Aves, Trochilidae) in the Colombian Orinoco region and comments of its distribution at the eastern Andes

Land use change and anthropic colonization influence forest degradation and biodiversity turnover. We present the first documented record of the Rufous-tailed Hummingbird, Amazilia tzacatl, for the eastern slope of the Andes-Orinoco region of Colombia. This hummingbird is widely known as a “non-forest” species in lowlands in the west of the Andes. We discuss recent observations in the eastern Andes. These records could be associated with land use change and deforestation fronts through the Andes

First documented record of Amazilia tzacatl (de la Llave, 1893) (Aves, Trochilidae) in the Colombian Orinoco region and comments of its distribution at the eastern Andes

Land use change and anthropic colonization influence forest degradation and biodiversity turnover. We present the first documented record of the Rufous-tailed Hummingbird, Amazilia tzacatl, for the eastern slope of the Andes-Orinoco region of Colombia. This hummingbird is widely known as a “non-forest” species in lowlands in the west of the Andes. We discuss recent observations in the eastern Andes. These records could be associated with land use change and deforestation fronts through the Andes

First documented record of Amazilia tzacatl (de la Llave, 1893) (Aves, Trochilidae) in the Colombian Orinoco region and comments of its distribution at the eastern Andes

Land use change and anthropic colonization influence forest degradation and biodiversity turnover. We present the first documented record of the Rufous-tailed Hummingbird, Amazilia tzacatl, for the eastern slope of the Andes-Orinoco region of Colombia. This hummingbird is widely known as a “non-forest” species in lowlands in the west of the Andes. We discuss recent observations in the eastern Andes. These records could be associated with land use change and deforestation fronts through the Andes

Global COVID-19 lockdown highlights humans as both threats and custodians of the environment

The global lockdown to mitigate COVID-19 pandemic health risks has altered human interactions with nature. Here, we report immediate impacts of changes in human activities on wildlife and environmental threats during the early lockdown months of 2020, based on 877 qualitative reports and 332 quantitative assessments from 89 different studies. Hundreds of reports of unusual species observations from around the world suggest that animals quickly responded to the reductions in human presence. However, negative effects of lockdown on conservation also emerged, as confinement resulted in some park officials being unable to perform conservation, restoration and enforcement tasks, resulting in local increases in illegal activities such as hunting. Overall, there is a complex mixture of positive and negative effects of the pandemic lockdown on nature, all of which have the potential to lead to cascading responses which in turn impact wildlife and nature conservation. While the net effect of the lockdown will need to be assessed over years as data becomes available and persistent effects emerge, immediate responses were detected across the world. Thus, initial qualitative and quantitative data arising from this serendipitous global quasi-experimental perturbation highlights the dual role that humans play in threatening and protecting species and ecosystems. Pathways to favorably tilt this delicate balance include reducing impacts and increasing conservation effectiveness

Volumen I. Catálogo de Biodiversidad para la Región Orinoquense

Bogotá, D. C.Instituto de Investigación de Recursos Biológicos Alexander von Humbold

Exploring the Catalytic Mechanism of Alkanesulfonate Monooxygenase Using Molecular Dynamics

The complex mechanistic properties of alkanesulfonate monooxygenase (SsuD) provide a particular challenge for identifying catalytically relevant amino acids. In response, a joint computational and experimental study was conducted to further elucidate the SsuD mechanism. Extensive unbiased molecular dynamics (MD) simulations were performed for six SsuD systems: (1) substrate-free, (2) bound with FMNH2, (3) bound with a C4a-peroxyflavin intermediate (FMNOO(-)), (4) bound with octanesulfonate (OCS), (5) co-bound with FMNH2 and OCS, and (6) co-bound with FMNOO(-) and OCS. A previous theoretical study suggested that salt bridges between Arg297 and Glu20 or Asp111 initiated conformational changes critical for catalysis. However, our MD simulations and steady-state kinetic experiments did not corroborate this result. Similar kcat/Km values for both the E20A and D111A SsuD variants to wild-type SsuD suggest that the salt bridges are not critical to the desulfonation mechanism. Instead, the predicted role of Arg297 is to favorably interact with the phosphate group of the reduced flavin. Concomitantly, Arg226 functioned as a "protection" group shielding FMNOO(-) from bulk solvent and was more pronounced when both FMNOO(-) and OCS were bound. The stabilization of FMNOO(-) through electrostatic interactions with Arg226 would properly position the C4a peroxy group for the proposed nucleophilic attack on the sulfur of octanesulfonate