Strong dependence of a pioneer shrub on seed dispersal services provided by an endemic endangered lizard in a Mediterranean island ecosystem

Es Colomer, a Unique Population of the Lilford's Wall Lizard, Podarcis lilfordi (Squamata: Lacertidae)

Es Colomer Island is occupied by a melanistic population of the Lilford's Wall lizard, Podarcis lilfordi. Adult males are larger than females, with longer tails, and higher values of body mass, pileus length, head heigh, head width, hindleg length and number of dorsal scales. Adult sex ratio is balanced or slightly skewed towards males. At the summit of the islet, body condition was found to be significantly better than in almost vertical slopes. We found a higher proportion of digit amputations in adult males, probably due to frequent male-male interactions, promoted by high lizard density. During a 2024 survey, we recorded the highest known density of the Lilford's Wall lizard. The prevalence of mites and blood parasites was 100%. The frequent intraspecific interactions, shown by the proportion of males with digit amputations, could be the source of the higher prevalence and susceptibility to blood parasite infections. The diet of lizards from Colomer is omnivorous, including several prey groups, as well as carcass remains from birds and mammals, and even conspecifics. Lizards from Colomer are an excellent example of the effects of extreme environmental conditions, with high population densities, strong intraspecific competition, the widespread presence of external and blood parasites, the extensive use of the scarce resources, and the opportunistic use of unpredictable resources in masting years, such as the fruits of the joint pine.

Ethnobotanical Uses and Pharmacological Activities of Moroccan Ephedra Species

Ephedra species are among the most popular herbs used in traditional medicine for a long time. The ancient Chinese medical book "Treatise on Febrile Diseases" refers to the classic traditional Chinese medicine prescription Ge Gen decoction, which consists of seven herbs, including an Ephedra species. Ephedra species are utilized all over the world to treat symptoms of the common cold and coughs, and to combat major human diseases, such as asthma, cancers, diabetes, cardiovascular and digestive disorders, and microbial infections. This study aimed at identifying specific Ephedra species used traditionally in Morocco for therapeutic purposes. The plant parts, their preparation process, and the treated pathologies were identified and analyzed. The results revealed five ethnobotanically important species of Ephedra: Ephedra alata Decne, Ephedra altissima Desf., Ephedra distachya L., Ephedra fragilis Desf., and Ephedra nebrodensis Tineo. These species are used traditionally in Morocco for treating people with diabetes, cancer, rheumatism, cold and asthma, hypertension, influenza virus infection, and respiratory ailments. In addition, they are occasionally used as calefacient agents, to regulate weight, or for capillary care. Few studies have underlined the antibacterial and antioxidant activities of some of these Moroccan Ephedra species, but little information is available regarding the natural products at the origin of the bioactivities. Further phytochemical investigations and clinical data are encouraged to better support the use of these plants.

Diversity patterns of lizard assemblages from a protected habitat mosaic in the Brazilian Cerrado savanna

Differences in habitat complexity and structure can directly influence the composition, diversity, and structure of species assemblages. Measurements of functional and phylogenetic diversity complement the commonly used measurements of taxonomic diversity, elucidating the relationships between species, their traits, and their evolutionary history. In this study, we evaluated how the mosaic of open and forested formations in a federal conservation unit in the western portion of the Brazilian Cerrado savanna influences the taxonomic, functional, and phylogenetic structure of lizard assemblages. Lizards were sampled for 15 months using pitfall traps set in open and forested formations. We recorded 292 lizards distributed among 16 species from eight families, with species composition differing among the formations. Richness was greater in the assemblages from open formations, while functional diversity and phylogenetic variability were greater in those of forested formations. Lizard assemblages in open formations were functionally and phylogenetically clustered, probably as a result of environmental filters acting on species, while the assemblages from forested formations were randomly structured. Different environmental and historical mechanisms have apparently shaped the current diversity of lizards in the region. This study shows that Cerrado vegetation mosaics can promote wide variation in different aspects of the taxonomic, functional, and phylogenetic structure from the lizard assemblages.

The effect of lizards on the dispersal and germination of Capparis spinosa (Capparaceae)

Seed dispersal is a key component of the interactions between plants and animals. There is little research on the effects of lizard seed dispersal, which is more common on islands than elsewhere. In this study, the effects of the passage of Capparis spinosa seeds through Teratoscincus roborowskii lizard digestive tracts on the seed coats, water uptake rates and germination rates were investigated. In addition, the spatial patterns of fecal deposition by lizards in various microhabitats were assessed. Our results showed that the mean retention time (MRT) of mealworms was significantly longer than that of C. spinosa seeds in both adult and juvenile lizards. The defecation rate of C. spinosa tended to be lower than that of mealworms, which might be beneficial for seed dispersal. It was determined that the longer MRT of C. spinosa seeds enhanced the permeability of the seed coats, which promoted fast water uptake, broke seed dormancy and increased the seed germination rate. Furthermore, the seeds that passed through the digestive tracts of lizards were deposited in favorable germination microhabitats. By enhancing seed germination and depositing intact and viable seeds in safe potential recruitment sites, the lizard T. roborowskii acts, at least qualitatively, as an effective disperser of C. spinosa.

Small size does not restrain frugivory and seed dispersal across the evolutionary radiation of Galápagos lava lizards

Frugivory in lizards is often assumed to be constrained by body size; only large individuals are considered capable of consuming fruits, with the potential of acting as seed dispersers. However, only one previous study has tested the correlation of frugivory with body and head size at an archipelago scale across closely related species. All nine lava lizards (Microlophus spp.) were studied on the eleven largest Galápagos islands from 2010 to 2016 to investigate whether frugivory is related to body and head size. We also tested whether fruit abundance influences fruit consumption and explored the effect of seed ingestion on seedling emergence time and percentage. Our results showed that across islands, lava lizards varied considerably in size (64-102 mm in mean snout-vent length) and level of frugivory (1-23%, i.e., percentage of droppings with seeds). However, level of frugivory was only weakly affected by size as fruit consumption was also common among small lizards. Lava lizards consumed fruits throughout the year and factors other than fruit abundance may be more important drivers of fruit selection (e.g., fruit size, energy content of pulp). From 2,530 droppings, 1,714 seeds of at least 61 plant species were identified, 76% of the species being native to the Galápagos. Most seeds (91%) showed no external structural damage. Seedling emergence time (44 versus 118 days) and percentage (20% versus 12%) were enhanced for lizard-ingested seeds compared to control (uningested) fruits. De-pulping by lizards (i.e., removal of pulp with potential germination inhibitors) might increase the chances that at least some seeds find suitable recruitment conditions. We concluded that lizards are important seed dispersers throughout the year and across the whole archipelago, regardless of body size.

Evidence for a double mutualistic interaction between a lizard and a Mediterranean gymnosperm, Ephedra fragilis

An increasing number of double mutualisms (i.e. two interacting species benefiting each other in two different functions, e.g. pollination and seed dispersal) have been reported, mainly from island ecosystems, although we still lack much information on how effective such species are in both processes. Here, we assessed the pollination effectiveness of a double mutualism between an ancient Mediterranean gymnosperm, Ephedra fragilis, and a lizard, Podarcis lilfordi. On the one hand, we assessed the lizard contribution to different fitness measures (seed set and germination success), relative to that of insects and the wind effect; on the other, we determined the lizards' seed removal rate (i.e. the quantity component of seed dispersal effectiveness). In both processes, we further tested for differences in their contributions among male, female and juvenile lizards. Ephedra fragilis showed to be mostly anemophilous, lizards and insects playing only a minor role on seed set. However, lizards qualitatively contributed to pollination success, as seeds coming from lizard-pollinated cones germinated at higher rates than those pollinated by wind or insects, although this was detected only for small seeds (<8 mg). The plant produced a low seed set (c. 23 %), which was compensated by a high seed germinability (c. 70 %). Adult male lizards were those most implicated in pollination, quantitatively more important than insects, and in seed dispersal. This work, thus, reports the importance of a lizard species in one of the few double mutualisms found in the World involving a gymnosperm, and it represents the first documentation of a double mutualism in the Mediterranean region. Our findings further contribute to highlight the role of both inter- and intraspecific differences in the effectiveness of mutualistic interactions.