Traditional management and morphological variation inLeucaena Esculenta (Fabaceae: Mimosoideae) in the mixtec region of Guerrero,Mexico

Ethnobotanical information about uses, management and traditional classification ofLeucaena esculenta by the Mixtec in Guerrero, Mexico, is presented. This plant is mainly used as human food. Buds of leaves and flowers as well as seeds and young pods are the main edible parts. Size, flavor and digestibility of seeds and pods are shown to be important in the Mixtec classification ofLeucaena species and in selection of trees to harvest during gathering. Artificial selection inL. esculenta subsp.esculenta by the Mixtec occurs not only under cultivation, but also in wild populations where people eliminate some individuals while promoting the growth of others with favorable phenotypes. Morphological characters of seeds and pods of individual trees of this subspecies were measured in order to compare phenotypic variation in populations subject to different regimes of management. Samples of trees were analyzed from a) a wild population not affected by intentional disturbances; b) a wild population selectively managed in situ; and c) a sample of cultivated individuals. Ordination methods and analysis of variance were used to examine differences between populations. A marked divergence between the three samples was found, especially between the wild populations managed and unmanaged. The frequency of the phenotypes preferred by people was found to be higher in the wild populationin situ managed. Our study confirms that through in situ forms of management, people are able to modify the phenotypic structure of plant populations. Possible routes of plant domestication within plant populationsin situ are suggested.     

The Domestication Syndrome in Phoenix dactylifera Seeds: Toward the Identification of Wild Date Palm Populations

Investigating crop origins is a priority to understand the evolution of plants under domestication, develop strategies for conservation and valorization of agrobiodiversity and acquire fundamental knowledge for cultivar improvement. The date palm (Phoenix dactylifera L.) belongs to the genus Phoenix, which comprises 14 species morphologically very close, sometimes hardly distinguishable. It has been cultivated for millennia in the Middle East and in North Africa and constitutes the keystone of oasis agriculture. Yet, its origins remain poorly understood as no wild populations are identified. Uncultivated populations have been described but they might represent feral, i.e. formerly cultivated, abandoned forms rather than truly wild populations. In this context, this study based on morphometrics applied to 1625 Phoenix seeds aims to (1) differentiate Phoenix species and (2) depict the domestication syndrome observed in cultivated date palm seeds using other Phoenix species as a “wild” reference. This will help discriminate truly wild from feral forms, thus providing new insights into the evolutionary history of this species. Seed size was evaluated using four parameters: length, width, thickness and dorsal view surface. Seed shape was quantified using outline analyses based on the Elliptic Fourier Transform method. The size and shape of seeds allowed an accurate differentiation of Phoenix species. The cultivated date palm shows distinctive size and shape features, compared to other Phoenix species: seeds are longer and elongated. This morphological shift may be interpreted as a domestication syndrome, resulting from the long-term history of cultivation, selection and human-mediated dispersion. Based on seed attributes, some uncultivated date palms from Oman may be identified as wild. This opens new prospects regarding the possible existence and characterization of relict wild populations and consequently for the understanding of the date palm origins. Finally, we here describe a pipeline for the identification of the domestication syndrome in seeds that could be used in other crops.     

Plant Management in the Tehuacán-Cuicatlán Valley, Mexico1

Plant Management in the Tehuacán-Cuicatlán Valley, Mexico. Plant management types currently practiced in the Tehuacán-Cuicatlán Valley, México, were documented and analyzed based on ethnobotanical studies conducted in 13 villages with six indigenous groups and Mestizo people. The information was organized in a data base, and then detailed and guided to a consensus through six workshops carried out by ethnobotanists working in the area. From a total of 1,608 useful plant species, we identified 610 with at least one management type other than simple gathering. Managed species are mainly used as food, fodder, medicinal, and ornamental, and they belong to 101 plant families. The higher species numbers were recorded in Cactaceae, Asteraceae, Fabaceae, Crassulaceae, and Agavaceae. Nearly 60% of the managed species are native to the region and the rest are introduced from other regions of Mexico and the world. In total, 400 species are ex situ managed out of their natural environments through seed sowing and/or planting their vegetative propagules or entire young plants; 373 species are in situ managed in their natural habitats as follows: all these species are deliberately left standing during vegetation clearance, 76 species are also enhanced intentionally favoring their abundance through modifications of their habitat, or directly by planting their propagules, and 51 receive protection through regulations, particular strategies of extraction, and actions against herbivores, competitors, freezing, radiation, and drought. Most management forms involve artificial selection at different intensity levels. The information allows visualizing co-occurrence of incipient and advanced forms of management at different intensity levels within and among species, which helps to postulate testable hypotheses on factors influencing plant management and domestication in an important area for studying the origins of agriculture.     

The Archaic Diet in Mesoamerica: Incentive for Milpa Development and Species Domestication

The Archaic Diet in Mesoamerica: Incentive for Milpa Development and Species Domestication. One of the central questions in the development of Mesoamerican civilization is how the alimentary, agronomic, and ecological complementarities were achieved within the milpa agroecosystem, which is one of its more important and distinctive cultural elements. In the Mesoamerican center of origin of agriculture and domestication of plants, located in western Mexico, we inquired among Náhuatl communities about the ancient dishes prepared with wild plants that are part of their ancient foodways, and the tools and technology used to prepare them. We found that the wild progenitors of Agave spp., Zea mays L, Cucurbita argyrosperma Hort. Ex L.H. Bayley, Phaseolus spp., Capsicum annum L., Solanum lycopersicum L., Physalis phyladelphica Lam, Spondias purpurea L., Persea americana Mill., and Hyptis suaveolens (L.) Poit are consumed in dishes that remain in the present food culture of the poor peasants, and are prepared with techniques and tools that were available in the Archaic period: Sun drying, roasting, toasting, baking, cracking, grinding, crushing, fermenting, and soaking in plain water or in water with ash, using three–stone fireplaces, stone toasters, crushers, grinders, rock pits, and three types of earth ovens. A remarkable finding was that beans could be incorporated into the diet without boiling, but just by toasting, stone grinding, and baking in corn dough tamales. Results obtained suggest that the basic Mesoamerican diet could have been shaped before the species involved were domesticated. Its nutritional complementarity since the Archaic period could have been one of the incentives for the development of the milpa system and the domestication of its species, achieving in this way also their ecological and agronomical complementarity.     

High-Throughput Sequencing and Mutagenesis to Accelerate the Domestication of Microlaena stipoides as a New Food Crop

Global food demand, climatic variability and reduced land availability are driving the need for domestication of new crop species. The accelerated domestication of a rice-like Australian dryland polyploid grass, Microlaena stipoides (Poaceae), was targeted using chemical mutagenesis in conjunction with high throughput sequencing of genes for key domestication traits. While M. stipoides has previously been identified as having potential as a new grain crop for human consumption, only a limited understanding of its genetic diversity and breeding system was available to aid the domestication process. Next generation sequencing of deeply-pooled target amplicons estimated allelic diversity of a selected base population at 14.3 SNP/Mb and identified novel, putatively mutation-induced polymorphisms at about 2.4 mutations/Mb. A 97% lethal dose (LD₉₇) of ethyl methanesulfonate treatment was applied without inducing sterility in this polyploid species. Forward and reverse genetic screens identified beneficial alleles for the domestication trait, seed-shattering. Unique phenotypes observed in the M2 population suggest the potential for rapid accumulation of beneficial traits without recourse to a traditional cross-breeding strategy. This approach may be applicable to other wild species, unlocking their potential as new food, fibre and fuel crops.     

Brassica rapa Domestication: Untangling Wild and Feral Forms and Convergence of Crop Morphotypes

The study of domestication contributes to our knowledge of evolution and crop genetic resources. Human selection has shaped wild Brassica rapa into diverse turnip, leafy, and oilseed crops. Despite its worldwide economic importance and potential as a model for understanding diversification under domestication, insights into the number of domestication events and initial crop(s) domesticated in B. rapa have been limited due to a lack of clarity about the wild or feral status of conspecific noncrop relatives. To address this gap and reconstruct the domestication history of B. rapa, we analyzed 68,468 genotyping-by-sequencing-derived single nucleotide polymorphisms for 416 samples in the largest diversity panel of domesticated and weedy B. rapa to date. To further understand the center of origin, we modeled the potential range of wild B. rapa during the mid-Holocene. Our analyses of genetic diversity across B. rapa morphotypes suggest that noncrop samples from the Caucasus, Siberia, and Italy may be truly wild, whereas those occurring in the Americas and much of Europe are feral. Clustering, tree-based analyses, and parameterized demographic inference further indicate that turnips were likely the first crop type domesticated, from which leafy types in East Asia and Europe were selected from distinct lineages. These findings clarify the domestication history and nature of wild crop genetic resources for B. rapa, which provides the first step toward investigating cases of possible parallel selection, the domestication and feralization syndrome, and novel germplasm for Brassica crop improvement.     

Mutualism breakdown in breadfruit domestication

During the process of plant domestication, below-ground communities are rarely considered. Some studies have attempted to understand the changes in root symbionts owing to domestication, but little is known about how it influences mycorrhizal response in domesticated crops. We hypothesized that selection for above-ground traits may also result in decreased mycorrhizal abundance in roots. Breadfruit (Artocarpus sp.) has a long domestication history, with a strong geographical movement of cultivars from west to east across the Melanesian and Polynesian islands. Our results clearly show a decrease in arbuscular mycorrhizas (AMs) along a domestication gradient from wild to recently derived cultivars. We showed that the vesicular and arbuscular colonization rate decreased significantly in more recently derived breadfruit cultivars. In addition, molecular analyses of breadfruit roots indicated that AM fungal species richness also responded along the domestication gradient. These results suggest that human-driven selection for plant cultivars can have unintended effects on below-ground mutualists, with potential impacts on the stress tolerance of crops and long-term food security.     

A single origin and moderate bottleneck during domestication of soybean (Glycine max): implications from microsatellites and nucleotide sequences

Background and Aims

It is essential to illuminate the evolutionary history of crop domestication in order to understand further the origin and development of modern cultivation and agronomy; however, despite being one of the most important crops, the domestication origin and bottleneck of soybean (Glycine max) are poorly understood. In the present study, microsatellites and nucleotide sequences were employed to elucidate the domestication genetics of soybean.

Methods

The genomes of 79 landrace soybeans (endemic cultivated soybeans) and 231 wild soybeans (G. soja) that represented the species-wide distribution of wild soybean in East Asia were scanned with 56 microsatellites to identify the genetic structure and domestication origin of soybean. To understand better the domestication bottleneck, four nucleotide sequences were selected to simulate the domestication bottleneck.

Key Results

Model-based analysis revealed that most of the landrace genotypes were assigned to the inferred wild soybean cluster of south China, South Korea and Japan. Phylogeny for wild and landrace soybeans showed that all landrace soybeans formed a single cluster supporting a monophyletic origin of all the cultivars. The populations of the nearest branches which were basal to the cultivar lineage were wild soybeans from south China. The coalescent simulation detected a bottleneck severity of K′ = 2 during soybean domestication, which could be explained by a foundation population of 6000 individuals if domestication duration lasted 3000 years.

Conclusions

As a result of integrating geographic distribution with microsatellite genotype assignment and phylogeny between landrace and wild soybeans, a single origin of soybean in south China is proposed. The coalescent simulation revealed a moderate genetic bottleneck with an effective wild soybean population used for domestication estimated to be ≈2 % of the total number of ancestral wild soybeans. Wild soybeans in Asia, especially in south China contain tremendous genetic resources for cultivar improvement.     

Whole-genome assembly and resequencing reveal genomic imprint and key genes of rapid domestication in narrow-leafed lupin

Shifting from a livestock-based protein diet to a plant-based protein diet has been proposed as an essential requirement to maintain global food sustainability, which requires the increased production of protein-rich crops for direct human consumption. Meanwhile, the lack of sufficient genetic diversity in crop varieties is an increasing concern for sustainable food supplies. Countering this concern requires a clear understanding of the domestication process and dynamics. Narrow-leafed lupin (Lupinus angustifolius L.) has experienced rapid domestication and has become a new legume crop over the past century, with the potential to provide protein-rich seeds. Here, using long-read whole-genome sequencing, we assembled the third-generation reference genome for the narrow-leafed lupin cultivar Tanjil, comprising 20 chromosomes with a total genome size of 615.8 Mb and contig N50 = 5.65 Mb. We characterized the original mutation and putative biological pathway resulting in low seed alkaloid level that initiated the recent domestication of narrow-leafed lupin. We identified a 1133-bp insertion in the cis-regulatory region of a putative gene that may be associated with reduced pod shattering (lentus). A comparative analysis of genomic diversity in cultivars and wild types identified an apparent domestication bottleneck, as precisely predicted by the original model of the bottleneck effect on genetic variability in populations. Our results identify the key domestication genetic loci and provide direct genomic evidence for a domestication bottleneck, and open up the possibility of knowledge-driven de novo domestication of wild plants as an avenue to broaden crop plant diversity to enhance food security and sustainable low-carbon emission agriculture.     

Wine clarification from Spondias mombin L. pulp by hollow fiber membrane system

The aim of this work was to study the cajá (Spondias mombin L.) wine clarification using a hollow fiber membrane system. Two cajá wines clarified with bentonite clay were used for comparison. Transmembrane pressures of 0.40 and 0.60 bar were used. Ninety-five percent of cajá wine colors were reduced at both transmembrane pressures and 66% with bentonite clay clarification. Cajá wine clarified with the membrane process was light yellow; but cajá wine clarified with bentonite clay had a turbid appearance. This works showed that it is possible to clarify the cajá wine with the membrane process and that this process did not change the quality of the wine and retained color, aroma and flavor from the cajá fruits. The membrane clarification enables a continuous process for cajá wine production.     

Phenotype and animal domestication: A study of dental variation between domestic,wild, captive,hybrid and insular Sus scrofa

Background

Identifying the phenotypic responses to domestication remains a long-standing and important question for researchers studying its early history. The great diversity in domestic animals and plants that exists today bears testament to the profound changes that domestication has induced in their ancestral wild forms over the last millennia. Domestication is a complex evolutionary process in which wild organisms are moved to new anthropogenic environments. Although modern genetics are significantly improving our understanding of domestication and breed formation, little is still known about the associated morphological changes linked to the process itself. In order to explore phenotypic variation induced by different levels of human control, we analysed the diversity of dental size, shape and allometry in modern free-living and captive wild, wild x domestic hybrid, domestic and insular Sus scrofa populations.

Results

We show that domestication has created completely new dental phenotypes not found in wild boar (although the amount of variation amongst domestic pigs does not exceed that found in the wild). Wild boar tooth shape also appears to be biogeographically structured, likely the result of post-glacial recolonisation history. Furthermore, distinct dental phenotypes were also observed among domestic breeds, probably the result of differing types and intensity of past and present husbandry practices. Captivity also appears to impact tooth shape. Wild x domestic hybrids possess second molars that are strictly intermediate in shape between wild boar and domestic pigs (third molars, however, showing greater shape similarity with wild boar) while their size is more similar to domestic pigs. The dental phenotypes of insular Sus scrofa populations found on Corsica and Sardinia today (originally introduced by Neolithic settlers to the islands) can be explained either by feralization of the original introduced domestic swine or that the founding population maintained a wild boar phenotype through time.

Conclusions

Domestication has driven significant phenotypic diversification in Sus scrofa. Captivity (environmental control), hybridization (genome admixture), and introduction to islands all correspond to differing levels of human control and may be considered different stages of the domestication process. The relatively well-known genetic evolutionary history of pigs shows a similar complexity at the phenotypic level.

Electronic supplementary material

The online version of this article (doi:10.1186/s12862-014-0269-x) contains supplementary material, which is available to authorized users.     

In situ management and domestication of plants in Mesoamerica

BACKGROUND AND AIMS: Ethnobotanical studies in Mexico have documented that Mesoamerican peoples practise systems of in situ management of wild and weedy vegetation directed to control availability of useful plants. In situ management includes let standing, encouraging growing and protection of individual plants of useful species during clearance of vegetation, which in some cases may involve artificial selection. The aim of this study was to review, complement and re-analyse information from three case studies which examined patterns of morphological, physiological and genetic effects of artificial selection in plant populations under in situ management in the region. METHODS: Information on wild and in situ managed populations of the herbaceous weedy plants Anoda cristata and Crotalaria pumila, the tree Leucaena esculenta subsp. esculenta and the columnar cacti Escontria chiotilla, Polaskia chichipe and Stenocereus stellatus from Central Mexico was re-analysed. Analyses compared morphology and frequency of morphological variants, germination patterns, and population genetics parameters between wild and managed in situ populations of the species studied. Species of columnar cacti are under different management intensities and their populations, including cultivated stands of P. chichipe and S. stellatus, were also compared between species. KEY RESULTS: Significant differences in morphology, germination patterns and genetic variation documented between wild, in situ managed and cultivated populations of the species studied are associated with higher frequencies of phenotypes favoured by humans in managed populations. Genetic diversity in managed populations of E. chiotilla and P. chichipe is slightly lower than in wild populations but in managed populations of S. stellatus variation was higher than in the wild. However, genetic distance between populations was generally small and influenced more by geographic distance than by management. CONCLUSIONS: Artificial selection operating on in situ managed populations of the species analysed is causing incipient domestication. This process could be acting on any of the 600-700 plant species documented to be under in situ management in Mesoamerica. In situ domestication of plants could be relevant to understand early processes of domestication and current conditions of in situ conservation of plant genetic resources.     

The western Mediterranean region provided the founder population of domesticated narrow-leafed lupin

Key message

This study revealed that the western Mediterranean provided the founder population for domesticated narrow-leafed lupin and that genetic diversity decreased significantly during narrow-leafed lupin domestication.

Abstract

The evolutionary history of plants during domestication profoundly shaped the genome structure and genetic diversity of today’s crops. Advances in next-generation sequencing technologies allow unprecedented opportunities to understand genome evolution in minor crops, which constitute the majority of plant domestications. A diverse set of 231 wild and domesticated narrow-leafed lupin (Lupinus angustifolius L.) accessions were subjected to genotyping-by-sequencing using diversity arrays technology. Phylogenetic, genome-wide divergence and linkage disequilibrium analyses were applied to identify the founder population of domesticated narrow-leafed lupin and the genome-wide effect of domestication on its genome. We found wild western Mediterranean population as the founder of domesticated narrow-leafed lupin. Domestication was associated with an almost threefold reduction in genome diversity in domesticated accessions compared to their wild relatives. Selective sweep analysis identified no significant footprints of selection around domestication loci. A genome-wide association study identified single nucleotide polymorphism markers associated with pod dehiscence. This new understanding of the genomic consequences of narrow-leafed lupin domestication along with molecular marker tools developed here will assist plant breeders more effectively access wild genetic diversity for crop improvement.

     

An Integrated Hypothesis on the Domestication of Bactris gasipaes

Peach palm (Bactris gasipaes Kunth) has had a central place in the livelihoods of people in the Americas since pre-Columbian times, notably for its edible fruits and multi-purpose wood. The botanical taxon includes both domesticated and wild varieties. Domesticated var gasipaes is believed to derive from one or more of the three wild types of var. chichagui identified today, although the exact dynamics and location of the domestication are still uncertain. Drawing on a combination of molecular and phenotypic diversity data, modeling of past climate suitability and existing literature, we present an integrated hypothesis about peach palm’s domestication. We support a single initial domestication event in south western Amazonia, giving rise to var. chichagui type 3, the putative incipient domesticate. We argue that subsequent dispersal by humans across western Amazonia, and possibly into Central America allowed for secondary domestication events through hybridization with resident wild populations, and differential human selection pressures, resulting in the diversity of present-day landraces. The high phenotypic diversity in the Ecuadorian and northern Peruvian Amazon suggest that human selection of different traits was particularly intense there. While acknowledging the need for further data collection, we believe that our results contribute new insights and tools to understand domestication and dispersal patterns of this important native staple, as well as to plan for its conservation.     

2012年第11期《遗传》封面说明

作物的驯化是人类从开始种植和储存的野生作物中选择优良性状,使之形态特征适应于农业生产方向进化的过程,因此,大部分种子作物驯化后在落粒性、种子休眠和植株形态等方面都出现了相似的变化。水稻是研究谷类作物驯化的良好模式生物。稻属包含2种栽培稻,分别为亚洲栽培稻(Oryza sativa L.)和非洲栽培稻(O. glaberrima Steud.),其中亚洲栽培稻遍布全世界,包含两个主要亚种,粳稻亚种(O. sativa L. ssp. japonica)和籼稻亚种(O. sativa L. ssp. indica)。稻属丰富的近缘种和广泛的地域分布非常有利于研究确定现代栽培稻的驯化地域。此外,水稻基因组较小、具高质量精细图谱,加上功能基因研究上的进展,也为深入开展水稻驯化进程研究奠定了基础。详见本期第XX-XX页区树俊,汪鸿儒,储成才“亚洲栽培稻主要驯化性状研究进展”,对水稻关键驯化性状研究进行的比较全面的综述。封面图中央是选取23株AA基因组的亚洲栽培稻及其近缘野生稻,利用水稻驯化过程中受到选择的控制稻壳颜色基因Bh4上下游各50 kb中的SNP位点所构建的进化树;图外从左下至右下沿顺时针方向,反映的是水稻驯化过程中稻壳颜色、谷粒形状、穗型的变化趋势。 区树俊,汪鸿儒,储成才（绘图：区树俊）     

Contrasting Mode of Evolution at a Coat Color Locus in Wild and Domestic Pigs

Despite having only begun ~10,000 years ago, the process of domestication has resulted in a degree of phenotypic variation within individual species normally associated with much deeper evolutionary time scales. Though many variable traits found in domestic animals are the result of relatively recent human-mediated selection, uncertainty remains as to whether the modern ubiquity of long-standing variable traits such as coat color results from selection or drift, and whether the underlying alleles were present in the wild ancestor or appeared after domestication began. Here, through an investigation of sequence diversity at the porcine melanocortin receptor 1 (MC1R) locus, we provide evidence that wild and domestic pig (Sus scrofa) haplotypes from China and Europe are the result of strikingly different selection pressures, and that coat color variation is the result of intentional selection for alleles that appeared after the advent of domestication. Asian and European wild boar (evolutionarily distinct subspecies) differed only by synonymous substitutions, demonstrating that camouflage coat color is maintained by purifying selection. In domestic pigs, however, each of nine unique mutations altered the amino acid sequence thus generating coat color diversity. Most domestic MC1R alleles differed by more than one mutation from the wild-type, implying a long history of strong positive selection for coat color variants, during which time humans have cherry-picked rare mutations that would be quickly eliminated in wild contexts. This pattern demonstrates that coat color phenotypes result from direct human selection and not via a simple relaxation of natural selective pressures.     

Molecular evidence for the origin and evolutionary history of the rare American desert monotypic family Setchellanthaceae

Setchellanthus caeruleus, which has disjunct populations in the north of the Chihuahuan Desert and in the Tehuacán-Cuicatlán valley, was selected to understand the evolutionary history of plants in this desert and its southerly relicts. This species constitutes the monotypic family Setchellanthaceae, which forms part of a group of plants that produce mustard-oil glucosides or glucosinolates. Molecular phylogenetic analyses based on DNA plastid sequences of plants of S. caeruleus from both areas, including representative taxa of the order Brassicales, were carried out to estimate the time of origin of the family (based on matK?+?rcbL) and divergence of populations (based on psbI-K, trnh-psbA, trnL-trnF). In addition, comparative ecological niche modelling was performed to detect if climate variables vary significantly in northern and southern populations. Analyses revealed that Setchellanthaceae is an ancient lineage that originated between 78 and 112 Mya during the mid-late Cretaceous—much earlier than the formation of the Chihuahuan Desert. The molecular data matrix displayed a few indel events as the only differences of plastid DNA sequences between northern and southern populations. It is suggested that due to climate changes in this desert in the Pliocene, populations of Setchellanthus remained in the Sierra de Jimulco and in Cuicatlán, in climatically stable locations. Ecological niche models of northern populations predict niches of southern populations and identity niche tests indicate that there are no differences in their ecological niches.     

Geography and end use drive the diversification of worldwide winter rye populations

To meet the current challenges in human food production, improved understanding of the genetic diversity of crop species that maximizes the selection efficacy in breeding programs is needed. The present study offers new insights into the diversity, genetic structure and demographic history of cultivated rye (Secale cereale L.). We genotyped 620 individuals from 14 global rye populations with a different end use (grain or forage) at 32 genome‐wide simple sequence repeat markers. We reveal the relationships among these populations, their sizes and the timing of domestication events using population genetics and model‐based inference with approximate Bayesian computation. Our main results demonstrate (i) a high within‐population variation and genetic diversity, (ii) an unexpected absence of reduction in diversity with an increasing improvement level and (iii) patterns suggestive of multiple domestication events. We suggest that the main drivers of diversification of winter rye are the end use of rye in two early regions of cultivation: rye forage in the Mediterranean area and grain in northeast Europe. The lower diversity and stronger differentiation of eastern European populations were most likely due to more intensive cultivation and breeding of rye in this region, in contrast to the Mediterranean region where it was considered a secondary crop or even a weed. We discuss the relevance of our results for the management of gene bank resources and the pitfalls of inference methods applied to crop domestication due to violation of model assumptions and model complexity.     

Learning interspecific communicative responses in Pampas foxes (Lycalopex gymnocercus)

Domestic dogs show remarkable communicative abilities in their interaction with people. These skills maybe explained by the interaction between the domestication process and learning experiences during ontogeny. Studies carried out on other species of canids, which have not been domesticated are relevant to this topic. The purpose of this article is to study the effect of instrumental learning on captive Pampas foxes’ (Lycalopex gymnocercus) communicative responses to humans. Seven foxes were tested in a conflict situation involving food within sight but out of their reach. In these situations dogs typically gaze at the human face to ask for food. In Study 1, there was an increase in gaze duration as a consequence of reinforcement and a decrease during extinction, when animals did not receive any more food. In Study 2, all of the four foxes tested successfully followed proximal pointing gesture to find hidden food. When a distal pointing cue was given, three out of four followed it in the first session and one in the second session. These results are consistent with those previously found in dogs, and suggest that learning experiences allow the development of communicative skills, even in not domesticated canid species.