lunes, 25 de marzo de 2024

lunes, 18 de marzo de 2024

Interaction network structure explains species’ temporal persistence in empirical plant–pollinator communities

Domínguez-Garcia et al., 2024.


Despite clear evidence that some pollinator populations are declining, our ability to predict pollinator communities prone to collapse or species at risk of local extinction is remarkably poor. Here, we develop a model grounded in the structuralist approach that allows us to draw sound predictions regarding the temporal persistence of species in mutualistic networks. Using high-resolution data from a six-year study following 12 independent plant–pollinator communities, we confirm that pollinator species with more persistent populations in the field are theoretically predicted to tolerate a larger range of environmental changes. Persistent communities are not necessarily more diverse, but are generally located in larger habitat patches, and present a distinctive combination of generalist and specialist species resulting in a more nested structure, as predicted by previous theoretical work. Hence, pollinator interactions directly inform about their ability to persist, opening the door to use theoretically informed models to predict species’ fate within the ongoing global change.


Despite clear evidence that some pollinator populations are declining, our
ability to predict pollinator communities prone to collapse or species at risk
of local extinction is remarkably poor. Here, we develop a model grounded
in the structuralist approach that allows us to draw sound predictions
regarding the temporal persistence of species in mutualistic networks.
Using high-resolution data from a six-year study following 12 independent
plant–pollinator communities, we confirm that pollinator species with more
persistent populations in the field are theoretically predicted to tolerate
a larger range of environmental changes. Persistent communities are not
necessarily more diverse, but are generally located in larger habitat patches,
and present a distinctive combination of generalist and specialist species
resulting in a more nested structure, as predicted by previous theoretical
work. Hence, pollinator interactions directly inform about their ability to
persist, opening the door to use theoretically informed models to predict
species’ fate within the ongoing global change.
Despite clear evidence that some pollinator populations are declining, our
ability to predict pollinator communities prone to collapse or species at risk
of local extinction is remarkably poor. Here, we develop a model grounded
in the structuralist approach that allows us to draw sound predictions
regarding the temporal persistence of species in mutualistic networks.
Using high-resolution data from a six-year study following 12 independent
plant–pollinator communities, we confirm that pollinator species with more
persistent populations in the field are theoretically predicted to tolerate
a larger range of environmental changes. Persistent communities are not
necessarily more diverse, but are generally located in larger habitat patches,
and present a distinctive combination of generalist and specialist species
resulting in a more nested structure, as predicted by previous theoretical
work. Hence, pollinator interactions directly inform about their ability to
persist, opening the door to use theoretically informed models to predict
species’ fate within the ongoing global change.

lunes, 11 de marzo de 2024

Lynn Margulis presents the Gaia Hypothesis at NASA (1984)

miércoles, 6 de marzo de 2024

Disruption of an ant-plant mutualism shapes interactions between lions and their primary prey

Kamaru et al., 2024

Mutualisms often define ecosystems, but they are susceptible to human activities. Combining experiments, animal tracking, and mortality investigations, we show that the invasive big-headed ant (Pheidole megacephala) makes lions (Panthera leo) less effective at killing their primary prey, plains zebra (Equus quagga). Big-headed ants disrupted the mutualism between native ants (Crematogaster spp.) and the dominant whistling-thorn tree (Vachellia drepanolobium), rendering trees vulnerable to elephant (Loxodonta africana) browsing and resulting in landscapes with higher visibility. Although zebra kills were significantly less likely to occur in higher-visibility, invaded areas, lion numbers did not decline since the onset of the invasion, likely because of prey-switching to African buffalo (Syncerus caffer). We show that by controlling biophysical structure across landscapes, a tiny invader reconfigured predator-prey dynamics among iconic species.


https://www.science.org/doi/10.1126/science.adg1464


martes, 27 de febrero de 2024

Coevolution of relationship and interaction in cooperative dynamical multiplex networks

Xiong et al., 2024.

While actors in a population can interact with anyone else freely, social relations significantly influence our inclination toward particular individuals. The consequence of such interactions, however, may also form the intensity of our relations established earlier. These dynamical processes are captured via a coevolutionary model staged in multiplex networks with two distinct layers. In a so-called relationship layer, the weights of edges among players may change in time as a consequence of games played in the alternative interaction layer. As an reasonable assumption, bilateral cooperation confirms while mutual defection weakens these weight factors. Importantly, the fitness of a player, which basically determines the success of a strategy imitation, depends not only on the payoff collected from interactions, but also on the individual relationship index calculated from the mentioned weight factors of related edges. Within the framework of weak prisoner’s dilemma situation, we explore the potential outcomes of the mentioned coevolutionary process where we assume different topologies for relationship layer. We find that higher average degree of the relationship graph is more beneficial to maintain cooperation in regular graphs, but the randomness of links could be a decisive factor in harsh situations. Surprisingly, a stronger coupling between relationship index and fitness discourage the evolution of cooperation by weakening the direct consequence of a strategy change. To complete our study, we also monitor how the distribution of relationship index vary and detect a strong relation between its polarization and the general cooperation level.


https://n9.cl/3n5vs


sábado, 17 de febrero de 2024

Two teosintes made modern maize 

Yang et al., 2023 

Extensive population and quantitative genetic analysis of domesticated maize and its wild relatives uncovered a substantial role for two different wild taxa in making modern maize. It is propose a new model for the origin of maize that can explain both genetic and archaeological data, and it is show how variation in Zea mays ssp. mexicana is a key component of maize diversity, both at individual loci and for genetic variation underlying agronomic traits.

The model raises a number of questions about how and why a secondary spread of maize may have occurred, but it is speculate that the timing of admixture suggests a possible direct role for hybridization between maize and Zea mays ssp. mexicana in improving early domesticated forms of maize, helping to transform it into the staple crop we know today.


Admixture analysis reveals widespread contributions of two teosintes to modern maize. (A) Proportion of highland teosinte admixture for traditional maize varieties across the Americas. (B) Admixture graph representing our model of maize evolution. (C) Cartoon depiction of proposed maize domestication and dispersal. (D) Characterization of admixture tracts along maize genomes. (E) Admixture for cob weight reveals a peak on chromosome 1.

https://www.science.org/doi/10.1126/science.adg8940



sábado, 10 de febrero de 2024

Assessing critical thresholds in terrestrial microbiomes  

Egidi et al., 2023.

Critical thresholds are abrupt changes in ecosystems triggered by environmental disturbances, which can be used to assess resilience and vulnerability. It is propose how a trait-based approach could be used to harness the predictive power of microbial dynamics to manage ecosystem response to environmental changes.



https://www.nature.com/articles/s41564-023-01536-2


lunes, 5 de febrero de 2024

lunes, 29 de enero de 2024

We often talk about conservation in the context of species. But it’s the interactions which are the glue that holds the entire system together.

Todd Palmer

(https://n9.cl/fo6rx)


viernes, 19 de enero de 2024

Science Before Statistics: Causal Inference  

Richard McElreath