domingo, 12 de mayo de 2024

 Introducción la selección natural


¿Cómo es posible un diseño sin un diseñador?  

En este conjunto de videos se le da respuesta a esta pregunta.

Para esto se parte de ideas intuitivas simples, las cuales una vez formalizadas en lenguaje matemático, permiten demostrar cómo surgen diseños en la naturaleza, sin la necesidad de que detrás de estos se encuentre un diseñador.

https://n9.cl/r2zsu4

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martes, 23 de abril de 2024

Can mutualists foster coexistence among resource competitors?

Mark McPeek

lunes, 15 de abril de 2024

miércoles, 10 de abril de 2024

 

Fungi, Forests, Group Selection (and Us?)

John Harte

martes, 2 de abril de 2024

Scaling up: microbiome manipulation for climate change adaptation in large organic vineyards

Carlos Pino and Diego Griffon

Regenerative agriculture offers important solutions to the enormous challenges that the climate crisis poses on food production. However, there are doubts about the possibility of implementing many of these solutions in a particularly important sector: the large scale. This paper addresses the issue, presenting examples of large-scale vineyard soil microbiome manipulation in Chile. The South American country has strongly faced the effects of climate change during the last decade and the organic viticulture sector is actively seeking strategies to adapt to the new climatic reality. Here the results of 4 experiments under real production conditions are shown. The experiments were designed to assess the effects of adding various microbial consortia to the soil on key agronomic parameters. Successful as well as unsuccessful cases are presented, allowing discussion of some conditions under which the microbiome manipulation can be expected to have positive effects. It was found that under good management conditions, incorporating effective microorganisms has positive effects on important production parameters (yield, root and vegetative growth). However, when fields yields are trending downward for prolonged periods, the incorporation of effective microbial consortia (e.g., antagonistic fungi, nutrient-fixing and nutrient-solubilizing bacteria) does not have a positive effect on the vineyard trend immediately. Similarly, even in favorable conditions the positive effects cannot be expected to be expressed in the short term (i.e., in just a few months). Therefore, its use should be conceived as a long-term strategy, not as an immediate solution to urgent management problems.

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