sábado, 7 de diciembre de 2019

viernes, 6 de diciembre de 2019

Coevolution Creates Complex Mosaics across Large Landscapes 
Fernande et al., 2019.

The spatial distribution of populations can influence the evolutionary outcome of species interactions. The variation in direction and strength of selection across local communities creates geographic selection mosaics that, when combined with gene flow and genomic processes such as genome duplication or hybridization, can fuel ongoing coevolution. A fundamental problem to solve is how coevolution proceeds when many populations that vary in their ecological outcomes are connected across large landscapes. Here we use a lattice model to explore this problem. Our results show that the complex interrelationships among the elements of the geographic mosaic of coevolution can lead to the formation of clusters of populations with similar phenotypes that are larger than expected by local selection. Our results indicate that neither the spatial distribution of phenotypes nor the spatial differences in magnitude and direction of selection alone dictate coevolutionary dynamics: the geographic mosaic of coevolution affects formation of phenotypic clusters, which in turn affect the spatial and temporal dynamics of coevolution. Because the formation of large phenotypic clusters depends on gene flow, we predict that current habitat fragmentation will change the outcomes of geographic mosaics, coupling spatial patterns in selection and phenotypes.


domingo, 1 de diciembre de 2019

Utricularia gibba, a freshwater carnivorous plant 
Photo: Igor Siwanowicz

sábado, 30 de noviembre de 2019

A global synthesis reveals biodiversity-mediated benefits for crop production       

Dainese et al., 2019

Human land use threatens global biodiversity and compromises multiple ecosystem functions critical to food production. Whether crop yield–related ecosystem services can be maintained by a few dominant species or rely on high richness remains unclear. Using a global database from 89 studies (with 1475 locations), we partition the relative importance of species richness, abundance, and dominance for pollination; biological pest control; and final yields in the context of ongoing land-use change. Pollinator and enemy richness directly supported ecosystem services in addition to and independent of abundance and dominance. Up to 50% of the negative effects of landscape simplification on ecosystem services was due to richness losses of service-providing organisms, with negative consequences for crop yields. Maintaining the biodiversity of ecosystem service providers is therefore vital to sustain the flow of key agroecosystem benefits to society.

Distribution of analyzed studies and effects of richness on ecosystem services provisioning.(A) Map showing the size (number of crop fields sampled) and location of the 89 studies (further details of studies are given in table S1). (B) Global effect of pollinator richness on pollination (n = 821 fields of 52 studies). (C) Global effect of natural enemy richness on pest control (n = 654 fields of 37 studies). The thick line in each plot represents the median of the posterior distribution of the model. Light gray lines represent 1000 random draws from the posterior. The lines are included to depict uncertainty of the modeled relationship.


jueves, 28 de noviembre de 2019

Los campos de trigo no me recuerdan nada y eso me pone triste.

El principito, Antoine de Saint-Exupéry.

miércoles, 27 de noviembre de 2019

Written in the Trees: The Roots of Arborglyphs 

"Since earliest times, trees – symbolically anchored in the earth and stretched towards the cosmos – have been inherently connected with human identity.”

Words and symbols carved onto a living tree are sometimes described as ‘arborglyphs’ (derived from arbor ‘tree’; glyphein ‘to carve’), but some people think of it vandalism or ‘tree graffiti’. Whatever the name, tree writing is driven by multifarious social and cultural factors; love, solitude, rivalry, identity, artistry, boredom, or downright bragging.

Arborglyphs are present across many cultures. In Australia the Gamilaroi and Wiradjuri peoples carved ceremonial trees to connect with ancestors. The Scorpion Tree of the Chumash people is thought to be an astrological tool whilst the Moriori people on Chatham Islands carved symbols of the natural world and faces of their ancestors into kopi trees.

As agriculture developed over time carved trees become landscape noticeboards, trail-markers or shelter. For global romantics, the gesture of carving a lover’s initials into a tree appeared as far back as Ovid’s Heroides:

‘The beech trees guard my name, cut there by you;
and I read ‘Oenone’, written there by your knife.

And as the trunk grows, my name grows the same;
grow, and rise straight, in honour of my name!’


lunes, 25 de noviembre de 2019

Utsutsunaki tsumami gokoro no kocho kana

Nothing actual,
the feeling of holding in my fingers
a butterfly.

Yosa Buson
Stick insect eggs
James Robertson 

sábado, 23 de noviembre de 2019

Mapping the dynamics of research networks in ecology and evolution using co-citation analysis (1975–2015)  
Reale et al., 2019.

In this paper we used a co-citation network analysis to quantify and illustrate the dynamic patterns of research in ecology and evolution over 40 years (1975–2014). We addressed questions about the historical patterns of development of these two fields. Have ecology and evolution always formed a coherent body of literature? What ideas have motivated research activity in subfields, and how long have these ideas attracted the attention of the scientific community? Contrary to what we expected, we did not observe any trend towards a stronger integration of ecology and evolution into one big cluster that would suggest the existence of a single community. Three main bodies of literature have stayed relatively stable over time: population/community ecology, evolutionary ecology, and population/quantitative genetics. Other fields disappeared, emerged or mutated over time. Besides, research organization has shifted from a taxon-oriented structure to a concept-oriented one over the years, with researchers working on the same topics but on different taxa showing more interactions.


viernes, 22 de noviembre de 2019

Measuring What Matters: Actionable Information for Conservation Biocontrol in Multifunctional Landscapes 
Chaplin-Kramer et al., 2019

Despite decades of study, conservation biocontrol via manipulation of landscape elements has not become a mainstream strategy for pest control. Meanwhile, conservation groups and governments rarely consider the impacts of land management on pest control, and growers can even fear that conservation biocontrol strategies may exacerbate pest problems. By finding leverage points among these actors, there may be opportunities to align them to promote more widespread adoption of conservation biological control at the landscape-scale. But are ecologists measuring the right things and presenting the right evidence to enable such alignment? We articulate key concerns of growers, conservation groups, and governments with regards to implementing conservation biological control at the landscape scale and argue that if ecologists want to gain more traction, we need to reconsider what we measure, for what goals, and for which audiences. A wider set of landscape objectives that ecologists should consider in our measurements include risk management for growers and co-benefits of multifunctional landscapes for public actors. Ecologists need to shift our paradigm toward longer-term, dynamic measurements, and build cross-disciplinary understanding with socioeconomic and behavioral sciences, to enable better integration of the objectives of these diverse actors that will be necessary for landscape management for conservation biocontrol to achieve its full potential.