scholarly journals Examining the link between relaxed predation and bird coloration on islands

2020 ◽  
Vol 16 (4) ◽  
pp. 20200002
Author(s):  
Louis Bliard ◽  
Matthieu Paquet ◽  
Aloïs Robert ◽  
Paul Dufour ◽  
Julien P. Renoult ◽  
...  
Keyword(s):  
Negative Relationship ◽  
Predation Pressure ◽  
Global Pattern ◽  
Pressure Relaxation ◽  
Island Syndrome ◽  
Insular Endemic ◽  
Insular Endemic Species ◽  
Bird Coloration ◽  
Insular Ecosystems ◽  
Phenotypic Responses

Insular ecosystems share analogous ecological conditions, leading to patterns of convergent evolution that are collectively termed as the ‘island syndrome’. In birds, part of this syndrome is a tendency for a duller plumage, possibly as a result of relaxed sexual selection. Despite this global pattern, some insular species display a more colourful plumage than their mainland relatives, but why this occurs has remained unexplained. Here, we examine the hypothesis that these cases of increased plumage coloration on islands could arise through a relaxation of predation pressure. We used comparative analyses to investigate whether average insular richness of raptors of suitable mass influences the plumage colourfulness and brightness across 110 pairs of insular endemic species and their closest mainland relatives. As predicted, we find a likely negative relationship between insular coloration and insular predation while controlling for mainland predation and coloration, suggesting that species were more likely to become more colourful as the number of insular predators decreased. By contrast, plumage brightness was not influenced by predation pressure. Relaxation from predation, together with drift, might thus be a key mechanism of species phenotypic responses to insularity.

A new insular, endemic frog of the genus Kalophrynus Tschudi, 1838 (Anura: Microhylidae) from Tioman Island, Pahang, Peninsular MalaysiaDepartment of Biology, La Sierra University, 4500 Riverwalk Parkway, Riverside, California, 92515-8247 USA.

Zootaxa ◽  
2011 ◽  
Vol 3123 (1) ◽  
pp. 60
Author(s):  
CHAN KIN ONN ◽  
L. LEE GRISMER ◽  
JESSE GRISMER
Keyword(s):  
Endemic Species ◽  
Peninsular Malaysia ◽  
Southeastern Coast ◽  
Insular Endemic ◽  
Insular Endemic Species

A new insular, endemic species of microhylid frog of the genus Kalophrynus is described from Tioman Island, off the southeastern coast of Pahang, Peninsular Malaysia. Kalophrynus tiomanensis sp nov. can be differentiated from its congeners by the following combination of characters: SVL 21.4–26.3 mm; reduced webbing on toes; outer metatarsal tubercle absent; large, black inguinal spot and unique markings on dorsum. This discovery increases the number of endemic species of amphibians on Tioman Island to at least three.

scholarly journals A global model of island species–area relationships

2019 ◽  
Vol 116 (25) ◽  
pp. 12337-12342 ◽  
Author(s):  
Thomas J. Matthews ◽  
François Rigal ◽  
Kostas A. Triantis ◽  
Robert J. Whittaker
Keyword(s):  
Species Richness ◽  
Structural Equation ◽  
Negative Relationship ◽  
Equation Model ◽  
Local Scale ◽  
Ecological Process ◽  
Global Pattern ◽  
Island Species ◽  
Species Area ◽  
Globally Distributed

The increase in species richness with island area (ISAR) is a well-established global pattern, commonly described by the power model, the parameters of which are hypothesized to vary with system isolation and to be indicative of ecological process regimes. We tested a structural equation model of ISAR parameter variation as a function of taxon, isolation, and archipelago configuration, using a globally distributed dataset of 151 ISARs encompassing a range of taxa and archipelago types. The resulting models revealed a negative relationship between ISAR intercept and slope as a function of archipelago species richness, in turn shaped by taxon differences and by the amount and disposition of archipelago area. These results suggest that local-scale (intra-archipelago) processes have a substantial role in determining ISAR form, obscuring the diversity patterns predicted by island theory as a function of archipelago isolation. These findings have implications for the use and interpretation of ISARs as a tool within biogeography, ecology, and conservation.

scholarly journals Isolation and predation drive gecko life-history evolution on islands

2020 ◽  
Vol 129 (3) ◽  
pp. 618-629
Author(s):  
Rachel Schwarz ◽  
Yuval Itescu ◽  
Antonis Antonopoulos ◽  
Ioanna-Aikaterini Gavriilidi ◽  
Karin Tamar ◽  
...  
Keyword(s):  
Life History ◽  
Life Histories ◽  
Life History Traits ◽  
Life History Evolution ◽  
Reproductive Traits ◽  
Predation Pressure ◽  
Ecological Studies ◽  
Island Populations ◽  
Island Syndrome ◽  
Insular Populations

Abstract Insular animals are thought to be under weak predation pressure and increased intraspecific competition compared with those on the mainland. Thus, insular populations are predicted to evolve ‘slow’ life histories characterized by fewer and smaller clutches of larger eggs, a pattern called the ‘island syndrome’. To test this pattern, we collected data on egg volume, clutch size and laying frequency of 31 Aegean Island populations of the closely related geckos of the Mediodactylus kotschyi species complex. We tested how predation pressure, resource abundance, island area and isolation influenced reproductive traits. Isolation and predation were the main drivers of variation in life-history traits. Higher predator richness seemed to promote faster life histories, perhaps owing to predation on adults, whereas the presence of boas promoted slower life histories, perhaps owing to release from predation by rats on the eggs of geckos. Insular geckos followed only some of the predictions of the ‘island syndrome’. Predation pressure seemed to be more complex than expected and drove life histories of species in two opposing directions. Our results highlight the importance of considering the identity of specific predators in ecological studies.

scholarly journals A new species of leaf-toed gecko (Phyllodactylidae, Phyllodactylus) from María Cleofas Island, Nayarit, Mexico

ZooKeys ◽  
2021 ◽  
Vol 1024 ◽  
pp. 117-136 ◽  
Author(s):  
Tonatiuh Ramírez-Reyes ◽  
Ilse K. Barraza-Soltero ◽  
Jose Rafael Nolasco-Luna ◽  
Oscar Flores-Villela ◽  
Armando H. Escobedo-Galván
Keyword(s):  
New Species ◽  
Biological Diversity ◽  
Morphological Evidence ◽  
Genetic Isolation ◽  
Unique Combination ◽  
Taxonomic Changes ◽  
Insular Endemic ◽  
Insular Endemic Species ◽  
A New Species ◽  
Insular Populations

We describe a new species of leaf-toed gecko of the genus Phyllodactylus from María Cleofas Island, the smallest island of Tres Marías Archipelago, Nayarit, México. Genomic, phylogenomic, and morphological evidence support that the new species presents a unique combination of diagnostic characters. Morphologically, the new species has a high number of tubercles, head to tail (mean 47), longitudinal ventral scales (mean 61), and third labial–snout scales (mean 26). Gene flow tests revealed the genetic isolation of insular populations from mainland counterparts. In addition, we confirmed the non-monophyly of P. homolepidurus and P. nolascoensis, and we show that the taxon P. t. saxatilis is a complex; therefore, we propose taxonomic changes within the saxatilis clade. The discovery of this new insular endemic species highlights the urgency of continued exploration of the biological diversity of island faunas of Mexico.

scholarly journals Global Pattern of Extended Education and Its Impact on Educational Outcomes: The Case of Science Education

2019 ◽  
Vol 7 (1-2019) ◽  
pp. 86-106 ◽  
Author(s):  
Sang Hoon Bae ◽  
Hyowon Park ◽  
Eun Ju Kwak ◽  
Eunwon Cho ◽  
Hyeonseok Jung
Keyword(s):  
Science Education ◽  
Science Achievement ◽  
National Level ◽  
Negative Relationship ◽  
Study Time ◽  
After School ◽  
Global Pattern ◽  
National Differences ◽  
The Individual ◽  
Extended Education

Science education as a part of STEM education is becoming important not only for the future success of the individual but also for the economic development of the nation. This study explores the global pattern of extended education and its impact on learning outcomes in the area of science. First, the study found substantial national differences in access to afterschool science programs. Children and youth in developing countries generally lack opportunities to learn science after school, which was found to predict PISA 2015 science achievement in this study. The study suggests that inequality in extended education among countries requires urgent attention, as does inequality within countries. Second, the study found a negative relationship between additional study time for science and PISA science performance at the national level. Regarding this finding, it is speculated that the content of learning during additional study time differs from that of higher-order learning experiences measured by the PISA science test. The result may also be explained by the argument that the purpose of additional afterschool study is usually remedial lessons and/or test preparation. This cross-national research will provide insights to policy makers who intend to find global patterns in extended education, develop policy direction at the global level, and offer advice to national governments.

A colorful new species of insular rock gecko (Cnemaspis Strauch 1887) from southern Vietnam

Zootaxa ◽  
2010 ◽  
Vol 2352 (1) ◽  
pp. 46 ◽  
Author(s):  
L. LEE GRISMER ◽  
NGO VAN TRI ◽  
JESSE L. GRISMER
Keyword(s):  
New Species ◽  
Endemic Species ◽  
Age Classes ◽  
Southern Vietnam ◽  
The Third ◽  
Bright Orange ◽  
Hands And Feet ◽  
Insular Endemic ◽  
Insular Endemic Species ◽  
A New Species

A new species of endemic, insular Cnemaspis is described from Hon Khoai Island, Ca Mau Province, Ngoc Hien District, 18 km off the southern tip of the Ca Mu Peninsula in southern Vietnam. Cnemaspis psychedelica sp. nov. is the most uniquely colored of all southeast Asian Cnemaspis in that both sexes and all age classes have bright orange forelimbs, forelegs, hands and feet; a bright orange tail; a dense, yellow reticulum on the neck overlying thick, black, longitudinal lines; and a blue-gray to light purple trunk bearing yellow transverse bars on bright-orange flanks. It also differs from all other species of Cnemaspis in aspects of size and squamation. Cnemaspis psychedelica is the third insular endemic species of Cnemaspis from Vietnam and brings the total number of species in Vietnam to six. Its occurrence on one of the 92 islands in Rach Gia Bay underscores the necessity for continued surveys of these poorly known islands that are beginning to show a surprising degree of endemism and diversity.

scholarly journals Large-scale phylogenomics reveals ancient introgression in Asian Hepatica and new insights into the origin of the insular endemic Hepatica maxima

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Seongjun Park ◽  
SeonJoo Park
Keyword(s):  
Endemic Species ◽  
Evolutionary History ◽  
Large Scale ◽  
Oceanic Islands ◽  
Network Analyses ◽  
Organellar Genomes ◽  
History Of ◽  
Insular Endemic ◽  
Insular Endemic Species ◽  
Hybridization And Introgression

Abstract Hepatica maxima is native to Ulleungdo, which is one of the oceanic islands in Korea, and it likely originated via anagenetic speciation from the Korean mainland species H. asiatica. However, the relationships among the Asian lineages remain unresolved. Phylogenomics based on plant genomes can provide new insights into the evolutionary history of plants. We first generated plastid, mitochondrial and transcriptome sequences of the insular endemic species H. maxima. Using the genomic data for H. maxima, we obtained a phylogenomic dataset consisting of 76 plastid, 37 mitochondrial and 413 nuclear genes from Asian Hepatica and two outgroups. Coalescent- and concatenation-based methods revealed cytonuclear and organellar discordance in the lineage. The presence of gynodioecy with cytoplasmic male sterility in Asian Hepatica suggests that the discordance is correlated with potential disruption of linkage disequilibrium between the organellar genomes. Species network analyses revealed a deep history of hybridization and introgression in Asian Hepatica. We discovered that ancient and recent introgression events occurred throughout the evolutionary history of the insular endemic species H. maxima. The introgression may serve as an important source of genetic variation to facilitate adaptation to the Ulleungdo environment.

scholarly journals In “defense” of Podarcis latastei, an Italian insular endemic species (Squamata: Lacertidae)

2021 ◽  
pp. 1-5
Author(s):  
Riccardo Castiglia ◽  
Gabriele Senczuk ◽  
Wolfgang Böhme ◽  
Claudia Corti
Keyword(s):  
Endemic Species ◽  
Morphological Evidence ◽  
Taxonomic Change ◽  
Pontine Islands ◽  
Insular Endemic ◽  
Insular Endemic Species

Abstract Based on genetic and morphological evidence, Senczuk et al. (2019) formally raised the Podarcis populations from the Western Pontine Islands, previously classified as several subspecies of P. siculus, to species rank, i.e. Podarcis latastei (Bedriaga, 1879). This taxonomic change was not accepted in the checklist of the European herpetofauna by Speybroeck et al. (2020), recently published on Amphibia-Reptilia. In this note we respond to the reasons given by Speybroeck and colleagues and support the validity of Podarcis latastei as an endemic Italian species.

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