Person:
López Teixido, Alberto

First Name

Alberto

Last Name

López Teixido

URI

https://hdl.handle.net/20.500.14352/87101

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Ciencias Biológicas

Department

Biodiversidad, Ecología y Evolución

Area

Botánica

Identifiers

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Search Results

Now showing 1 - 10 of 18

Intraspecific variation in fruit–frugivore interactions: effects of fruiting neighborhood and consequences for seed dispersal
(Oecologia, 2017) Guerra, Tadeu J.; Dayrell, Roberta L. C.; Arruda, André J.; Dáttilo, Wesley; López Teixido, Alberto; Messeder, João V. S.; Silveira, Fernando A. O.
The extent of specialization/generalization continuum in fruit–frugivore interactions at the individual level remains poorly explored. Here, we investigated the interactions between the Neotropical treelet Miconia irwinii (Melastomataceae) and its avian seed dispersers in Brazilian campo rupestre. We built an individual-based network to derive plant degree of interaction specialization regarding disperser species. Then, we explored how intraspecific variation in interaction niche breadth relates to fruit availability on individual plants in varying densities of fruiting conspecific neighbors, and how these factors affect the quantity of viable seeds dispersed. We predicted broader interaction niche breadths for individuals with larger fruit crops in denser fruiting neighborhoods. The downscaled network included nine bird species and 15 plants, which varied nearly five-fold in their degree of interaction specialization. We found positive effects of crop size on visitation and fruit removal rates, but not on degree of interaction specialization. Conversely, we found that an increase in the density of conspecific fruiting neighbors both increased visitation rate and reduced plant degree of interaction specialization. We suggest that tracking fruit-rich patches by avian frugivore species is the main driver of density-dependent intraspecific variation in plants’ interaction niche breadth. Our study shed some light on the overlooked fitness consequences of intraspecific variation in interaction niches by showing that individuals along the specialization/generalization continuum may have their seed dispersed with similar effectiveness. Our study exemplifies how individual-based networks linking plants to frugivore species that differ in their seed dispersal effectiveness can advance our understanding of intraspecific variation in the outcomes of fruit–frugivore interactions.
Large and abundant flowers increase indirect costs of corollas: a study of coflowering sympatric Mediterranean species of contrasting flower size
(Oecologia, 2013) López Teixido, Alberto; Valladares, Fernando
Large floral displays receive more pollinator visits but involve higher production and maintenance costs. This can result in indirect costs which may negatively affect functions like reproductive output. In this study, we explored the relationship between floral display and indirect costs in two pairs of coflowering sympatric Mediterranean Cistus of contrasting flower size. We hypothesized that: (1) corolla production entails direct costs in dry mass, N and P, (2) corollas entail significant indirect costs in terms of fruit set and seed production, (3) indirect costs increase with floral display, (4) indirect costs are greater in larger-flowered sympatric species, and (5) local climatic conditions influence indirect costs. We compared fruit set and seed production of petal-removed flowers and unmanipulated control flowers and evaluated the influence of mean flower number and mean flower size on relative fruit and seed gain of petal-removed and control flowers. Fruit set and seed production were significantly higher in petal-removed flowers in all the studied species. A positive relationship was found between relative fruit gain and mean individual flower size within species. In one pair of species, fruit gain was higher in the large-flowered species, as was the correlation between fruit gain and mean number of open flowers. In the other pair, the correlation between fruit gain and mean flower size was also higher in the large-flowered species. These results reveal that Mediterranean environments impose significant constraints on floral display, counteracting advantages of large flowers from the pollination point of view with increased indirect costs of such flowers.
Major biases and knowledge gaps on fragmentation research in Brazil: Implications for conservation
(Biological Conservation, 2020) López Teixido, Alberto; Gonçalves, Stela; Fernández-Arellano, Gileberto; Dáttilo, Wesley; Izzo, Thiago; Layme, Viviane; Moreira, Leonardo; Quintanilla, Luis
Habitat loss and fragmentation are among the main threats to global biodiversity and ecosystem services. However, major research biases and knowledge shortfalls in some geographical regions, taxonomic groups and responses studied are recurrent in fragmentation-related research. Therefore, detecting these biases and associated gaps is crucial to steer future research efforts and to guide applicable conservation policies. Here we conducted an exhaustive literature review to evaluate biases on fragmentation research across biomes, taxonomic groups, species responses and fragmentation metrics in Brazil. Overall, we analysed 716 papers, comprising a database with 26 taxonomic groups and 1173 cases studied across the six Brazilian biomes. In general, we observed that fragmentation-related research was biogeographically biased towards forest biomes. Specifically, the Atlantic Forest, the most populated and deforested Brazilian biome, comprised the highest number of studies (63%), while non-forest biomes were largely underrepresented. We also detected a high positive relative taxonomic bias for birds and mammals, while many insect taxa were disproportionately underrepresented in the literature. Altogether, assemblage-level species responses (abundance, diversity and richness) comprised 72% of study cases. Moreover, fragment size was clearly the most considered metric in the studies (43%) followed by habitat quality and edge effects. Our findings indicate major information deficits with regard to fragmentation-related research among taxonomic groups and amongst biomes in a megadiverse country. Therefore, we suggest that fragmentation research conducted in Brazil needs to consider undersampled taxa and to be urgently extended to increasingly degraded non-forest biomes in order to avoid inappropriate inferences.
Global homogenization of the structure and function in the soil microbiome of urban greenspaces
(Science Advances, 2021) Delgado-Baquerizo, Manuel; Eldridge, David J.; Liu, Yu-Rong; Sokoya, Blessing; Wang, Jun-Tao; Hu, Hang-Wei; He, Ji-Zheng; Bastida, Felipe; Moreno, José L.; Bamigboye, Adebola R.; Blanco-Pastor, José L.; Cano-Díaz, Concha; Illán, Javier G.; Makhalanyane, Thulani P.; Siebe, Christina; Trivedi, Pankaj; Zaady, Eli; Verma, Jay Prakash; Wang, Ling; Wang, Jianyong; Grebenc, Tine; Peñaloza-Bojacá, Gabriel F.; Nahberger, Tina U.; López Teixido, Alberto; Zhou, Xin-Quan; Berdugo, Miguel; Duran, Jorge; Rodríguez, Alexandra; Zhou, Xiaobing; Alfaro, Fernando; Abades, Sebastian; Plaza, César; Rey Muñoz, Ana Isabel; Singh, Brajesh K.; Tedersoo, Leho; Fierer, Noah
The structure and function of the soil microbiome of urban greenspaces remain largely undetermined. We conducted a global field survey in urban greenspaces and neighboring natural ecosystems across 56 cities from six continents, and found that urban soils are important hotspots for soil bacterial, protist and functional gene diversity, but support highly homogenized microbial communities worldwide. Urban greenspaces had a greater proportion of fast-growing bacteria, algae, amoebae, and fungal pathogens, but a lower proportion of ectomycorrhizal fungi than natural ecosystems. These urban ecosystems also showed higher proportions of genes associated with human pathogens, greenhouse gas emissions, faster nutrient cycling, and more intense abiotic stress than natural environments. City affluence, management practices, and climate were fundamental drivers of urban soil communities. Our work paves the way toward a more comprehensive global-scale perspective on urban greenspaces, which is integral to managing the health of these ecosystems and the well-being of human populations.
Environmental filtering controls soil biodiversity in wet tropical ecosystems
(Soil Biology and Biochemistry, 2022) Haiying Cui; Peter M. Vitousek; Sasha C. Reed; Wei Sun; Blessing Sokoya; Bamigboye, Adebola R.; Verma, Jay Prakash; Mukherjee, Arpan; Peñaloza-Bojacá, Gabriel F.; López Teixido, Alberto; Trivedi, Pankaj; He, Ji-Zheng; Hu, Hang-Wei; Png, Kenny; Delgado-Baquerizo, Manuel
The environmental factors controlling soil biodiversity along resource gradients remain poorly understood in wet tropical ecosystems. Aboveground biodiversity is expected to be driven by changes in nutrient availability in these ecosystems, however, much less is known about the importance of nutrient availability in driving soil biodiversity. Here, we combined a cross-continental soil survey across tropical regions with a three decades' field experiment adding nitrogen (N) and phosphorus (P) (100 kg N ha−1y−1 and 100 kg P ha−1y−1) to Hawai'ian tropical forests with contrasting substrate ages (300 and 4,100,000 years) to investigate the influence of nutrient availability to explain the biodiversity of soil bacteria, fungi, protists, invertebrates and key functional genes. We found that soil biodiversity was driven by soil acidification during long-term pedogenesis and across environmental gradients, rather than by nutrient limitations. In fact, our results showed that experimental N additions caused substantial acidification in soils from Hawai'i. These declines in pH were related to large decreases in soil biodiversity from tropical ecosystems in four continents. Moreover, the microbial activity did not change in response to long-term N and P additions. We concluded that environmental filtering drives the biodiversity of multiple soil organisms, and that the acidification effects associated with N additions can further create substantial undesired net negative effects on overall soil biodiversity in naturally tropical acid soils. This knowledge is integral for the understanding and management of soil biodiversity in tropical ecosystems globally.
Sex-dependent selection on flower size in a large-flowered Mediterranean species: an experimental approach with Cistus ladanifer
(Plant Systematics and Evolution, 2014) Barrio, Miguel; López Teixido, Alberto
Larger flowers increase pollinator visit rates and reproductive success, so selection on flower size is usually mediated by pollinators. However, larger flowers involve costs imposed by resource limitation so environmental conditions may also modulate flower size. “Male function” hypothesis entails that the intensity of selection is sex-dependent, being greater through male fitness, whereas female fitness is more limited by resources. In this study we analyse pollinator-mediated phenotypic selection on flower size through both sexes in a large-flowered Mediterranean species, Cistus ladanifer. We experimentally manipulated flower size in two populations, measured its effect on male and female fitness and estimated the strength and direction of phenotypic selection through both sexes and populations. Unmanipulated control flowers received higher pollinator visit rates and dispersed a higher pollen amount than reduced flowers. This translated into selection towards larger flowers through male fitness in both populations. Nevertheless, flower size had little effect on female fitness. Fruit set was high but selection through this component of female function was not significant. Seed number increased in control flowers, especially in one population, where we detected positive selection on flower size. Our results suggest that pollinator-mediated phenotypic selection on flower size in this large-flowered Mediterranean species is especially modulated by male fitness, but flower size adjustment may also be a result of a simultaneous selection through both sexes that, in turn, is dependent of ecological context.
Size Matters: Understanding the Conflict Faced by Large Flowers in Mediterranean Environments
(The Botanical Review, 2016) López Teixido, Alberto; Barrio, Miguel; Valladares, Fernando
Flower size is a key trait in the reproductive ecology of animal-pollinated plants. However, pollinator-mediated selection does not always modulate this trait and environmental conditions and/or antagonist interactions may favor smaller flowers. We evaluate the occurrence of a large-flowered family in a hot and dry Mediterranean environment, mediated by a cost-benefit balance and a male–female conflict. Large flowers have sizeable benefits in terms of pollination and reproductive success and pollinators mediate selection through male function, but female fitness is context-dependent. High floral production and maintenance costs and florivore incidence in large flowers limit female function, which counteracts pollinator-mediated selection. Large flowers are highly costly in the Mediterranean and flower size is mediated by a sexual conflict between the benefits of male function and the costs of the female one. However, a short floral longevity, occasional pollen limitation and selection through maleness keep the existence of large flowers in these environments.
Reproductive assurance weakens pollinator-mediated selection on flower size in an annual mixed-mating species
(Annals of Botany, 2019) López Teixido, Alberto; Aizen, Marcelo A.
Background and Aims In animal-pollinated plants, direct and indirect selection for large and small flowers in predominantly outcrossing and selfing species, respectively, is a common consequence of pollen limitation (PL). However, many hermaphroditic species show a mixed-mating system known as delayed selfing, which provides reproductive assurance (RA) only when outcrossing is not realized. Although RA is expected to reduce pollinator-mediated selection towards larger flowers, the consequences of delayed selfing for selection on flower size in mixed-mating species remain overlooked. We investigated whether RA weakens selection on flower size in Tuberaria guttata, a mixed-mating annual herb. Methods We related pollinator visitation rates to flower size and measured seed production in emasculated, hand cross-pollinated and intact (control) flowers in three natural populations. For each population, we estimated variation in PL and RA across individuals differing in flower size and phenotypic selection on this trait. Key Results Pollinator visitation increased and RA decreased with flower size in all populations. Increasing RA diminished but did not fully alleviate PL, because of early-acting inbreeding depression. In the least-visited and most pollen-limited population, RA increased seed production by >200 %, intensely counteracting the strong pollinator-mediated selection for larger corollas. In the most-visited population, however, RA increased seed production by an average of only 9 %. This population exhibited the largest fraction of individuals that showed a decrease in seed production due to selfing and the weakest pollinator-mediated selection on flower size. Conclusions The results suggest that the balance between the extent of RA and outcrossing contributes to determine flower size in mixed-mating systems. Pollinator-mediated selection favours larger flowers by increasing outcrossed seeds, but the benefits of RA greatly lessen this effect, especially under severe conditions of pollen limitation. Our findings also indicate that a mixed-mating system can represent an ‘evolutionary trap’ under an adequate pollinator supply.
Impacts of changes in land use and fragmentation patterns on Atlantic coastal forests in northern Spain
(Journal of Environmental Management, 2009) López Teixido, Alberto; García Quintanilla, Luis; Carreño, Francisco; Gutiérrez, David
Changes in forested landscapes may have important consequences for ecosystem services and biodiversity conservation. In northern Spain, major changes in land use occurred during the second half of the 20th century, but their impacts on forests have not been quantified. We evaluated the dynamics of landscape and forest distribution patterns between 1957 and 2003 in Fragas do Eume Natural Park (northwestern Spain). We used orthoimages and a set of standard landscape metrics to determine transitions between land cover classes and to examine forest distribution patterns. Eucalypt plantations showed the greatest increase in area (197%) over time. Furthermore, transitions to eucalypt plantations were found in all major land cover classes. Forest showed a net decline of 20% in total area and represented 30% of the landscape area in 2003. Forest losses were mainly due to eucalypt plantations and the building of a water reservoir, while forest gains were due to increases in shrubland, meadows and cultivated fields which had been recolonised. Forest patch size and core area decreased, and edge length increased over time. In turn, increases were obtained in mean distance between forest patches, and in adjacency to eucalypt plantations and to a water reservoir. These results suggest an increase in forest fragmentation from 1957 to 2003, as well as a change in the nature of the habitat surrounding forest patches. This study shows that land use changes, mostly from eucalypt plantation intensification, negatively affected forested habitats, although some regeneration was ongoing through ecological succession from land abandonment.
Assessing bias and knowledge gaps on seed ecology research: implications for conservation agenda and policy
(Ecological Applications, 2016) Ribeiro, Guilherme; López Teixido, Alberto; Barbosa, Newton; Silveira, Fernando
Sampling biases permeate ecological research and result in knowledge gaps that have vital consequences for conservation planning. The consequences of knowledge gaps on species identity and distribution (the Wallacean and Linnean shortfalls, respectively) have become apparent recently, but we know little about the extent that research biases and knowledge gaps on traits that influence species’ niches (the Hutchinsonian shortfall) affect conservation policy. To examine whether knowledge of species’ traits based on seed ecology is geographically, phylogenetically, and ecologically biased, we retrieved research data on seed germination, seed dormancy, seed dispersal, seed banks, seed predation, and seed removal from a database of 847 papers, 1648 species, and 5322 cases. Brazil was selected as a model system for megadiverse, undersampled countries. Kernel density maps showed that research was geographically biased towards highly populated sites, with vast areas remaining historically unexplored. We also show that research was clustered into protected areas. We detected a significant positive phylogenetic bias at genus-level, indicating research concentration in few genera and lower relative bias rates for many herbaceous genera. Unexpectedly, information on seed banking was available for only 74 (3.4%) of threatened species, which suggests that information deficits are highest for species with critical needs for ex situ conservation strategies. Tree, fleshy-fruited, and biotic dispersal species were disproportionately overstudied. Our data indicate that information deficits on seed ecology preclude our ability to effectively restore ecosystems and to safeguard endangered species. We call for a systematic improvement of environmental agenda in which policy makers and scientists target sites, clades, and functional groups historically neglected. Lessons from developed countries and collaborative efforts will be important for megadiverse, underdeveloped countries to achieve the targets of international agreements that depend on seed ecology knowledge aiming to secure biological diversity and ecosystem services.