A closer look at pupil diversity and evolution in frogs and toads

The eyes of frogs and toads (Anura) are among their most fascinating features. Although several pupil shapes have been described, the diversity, evolution, and functional role of the pupil in anurans have received little attention. Studying photographs of more than 3200 species, we surveyed pupil diversity, described their morphological variation, tested correlation with adult habits and diel activity, and discuss major evolutionary patterns considering iris anatomy and visual ecology. Our results indicate that the pupil in anurans is a highly plastic structure, with seven main pupil shapes that evolved at least 116 times during the history of the group. We found no significant correlation between pupil shape, adult habits, and diel activity, with the exception of the circular pupil and aquatic habits. The vertical pupil arose at least in the most-recent common ancestor of Anura + Caudata, and this morphology is present in most early-diverging anuran clades. Subsequently, a horizontal pupil, a very uncommon shape in vertebrates, evolved in most neobatrachian frogs. This shape evolved into most other known pupil shapes, but it persisted in a large number of species with diverse life histories, habits, and diel activity patterns, demonstrating a remarkable functional and ecological versatility.

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Nocturnality in synapsids predates the origin of mammals by over 100 million years

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.1642 ◽

2014 ◽

Vol 281 (1793) ◽

pp. 20141642 ◽

Cited By ~ 48

Author(s):

K. D. Angielczyk ◽

L. Schmitz

Keyword(s):

Evolutionary History ◽

Activity Patterns ◽

Early Evolution ◽

Late Carboniferous ◽

Diel Activity ◽

Ecological Diversity ◽

Behavioural Pattern ◽

Nocturnal Activity ◽

Diel Activity Patterns ◽

History Of

Nocturnality is widespread among extant mammals and often considered the ancestral behavioural pattern for all mammals. However, mammals are nested within a larger clade, Synapsida, and non-mammalian synapsids comprise a rich phylogenetic, morphological and ecological diversity. Even though non-mammalian synapsids potentially could elucidate the early evolution of diel activity patterns and enrich the understanding of synapsid palaeobiology, data on their diel activity are currently unavailable. Using scleral ring and orbit dimensions, we demonstrate that nocturnal activity was not an innovation unique to mammals but a character that appeared much earlier in synapsid history, possibly several times independently. The 24 Carboniferous to Jurassic non-mammalian synapsid species in our sample featured eye morphologies consistent with all major diel activity patterns, with examples of nocturnality as old as the Late Carboniferous ( ca 300 Ma). Carnivores such as Sphenacodon ferox and Dimetrodon milleri , but also the herbivorous cynodont Tritylodon longaevus were likely nocturnal, whereas most of the anomodont herbivores are reconstructed as diurnal. Recognizing the complexity of diel activity patterns in non-mammalian synapsids is an important step towards a more nuanced picture of the evolutionary history of behaviour in the synapsid clade.

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The integrin-mediated adhesome complex, essential to multicellularity, is present in the most recent common ancestor of animals, fungi, and amoebae

10.1101/2020.04.29.069435 ◽

2020 ◽

Author(s):

Seungho Kang ◽

Alexander K. Tice ◽

Courtney W. Stairs ◽

Daniel J. G. Lahr ◽

Robert E. Jones ◽

...

Keyword(s):

Critical Role ◽

Recent Common Ancestor ◽

Most Recent Common Ancestor ◽

Level Data ◽

Eukaryote Evolution ◽

History Of ◽

Unicellular Organisms ◽

Adhesion Complex ◽

Eukaryotic Supergroup

AbstractIntegrins are transmembrane receptor proteins that activate signal transduction pathways upon extracellular matrix binding. The Integrin Mediated Adhesion Complex (IMAC), mediates various cell physiological process. The IMAC was thought to be an animal specific machinery until over the last decade these complexes were discovered in Obazoa, the group containing animals, fungi, and several microbial eukaryote lineages. Amoebozoa is the eukaryotic supergroup sister to Obazoa. Even though Amoebozoa represents the closest outgroup to Obazoa, little genomic-level data and attention to gene inventories has been given to the supergroup. To examine the evolutionary history of the IMAC, we examine gene inventories of deeply sampled set of 100+ Amoebozoa taxa, including new data from several taxa. From these robust data sampled from the entire breadth of known amoebozoan clades, we show the presence of an ancestral complex of integrin adhesion proteins that predate the evolution of the Amoebozoa. Our results highlight that many of these proteins appear to have evolved earlier in eukaryote evolution than previously thought. Co-option of an ancient protein complex was key to the emergence of animal type multicellularity. The role of the IMAC in a unicellular context is unknown but must also play a critical role for at least some unicellular organisms.

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Activity patterns of wild Bactrian camels (Camelus bactrianus) in the northern piedmont of the Altun Mountains, China

Animal Biology ◽

10.1163/15707563-00002471 ◽

2015 ◽

Vol 65 (3-4) ◽

pp. 209-217 ◽

Cited By ~ 2

Author(s):

Yadong Xue ◽

Diqiang Li ◽

Wenfa Xiao ◽

Fang Liu ◽

Yuguang Zhang ◽

...

Keyword(s):

Seasonal Variation ◽

Endangered Species ◽

Activity Patterns ◽

Relative Activity ◽

Diel Activity ◽

Arid Areas ◽

Critically Endangered Species ◽

Camelus Bactrianus ◽

Diel Activity Patterns ◽

Bactrian Camels

There are significant gaps in our knowledge of wild camel ecology; especially the activity patterns that allow them to adapt to desert environments. The wild Bactrian camel (Camelus bactrianus) is a critically endangered species that survives in the extreme desert conditions of Central Asia. We conducted camera trapping surveys at seven watering sites in the northern piedmont of the Altun Mountains from 2010 to 2012. We analyzed the frequency of photo-captures to elucidate the wild camels’ diel activity patterns, and the seasonal variation in their activity at watering sites. We found that these wild camels were predominantly diurnal at watering sites, with an increase in relative activity from sunrise, reaching a peak toward midday, and then gradually decreasing in activity until sunset. The camels visited watering sites more often in winter than in summer. These results provide a guide for water development in the conservation of ungulates in arid areas.

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Testing the spatial and temporal framework of speciation in an ancient lake species flock: the leech genus <i>Dina</i> (Hirudinea: Erpobdellidae) in Lake Ohrid

Biogeosciences ◽

10.5194/bg-7-3387-2010 ◽

2010 ◽

Vol 7 (11) ◽

pp. 3387-3402 ◽

Cited By ~ 32

Author(s):

S. Trajanovski ◽

C. Albrecht ◽

K. Schreiber ◽

R. Schultheiß ◽

T. Stadler ◽

...

Keyword(s):

Molecular Clock ◽

Abiotic Factors ◽

Time Frame ◽

Recent Common Ancestor ◽

Species Flock ◽

Ancient Lake ◽

Lake Ohrid ◽

Most Recent Common Ancestor ◽

Extant Species

Abstract. Ancient Lake Ohrid on the Balkan Peninsula is considered to be the oldest ancient lake in Europe with a suggested Plio-/Pleistocene age. Its exact geological age, however, remains unknown. Therefore, molecular clock data of Lake Ohrid biota may serve as an independent constraint of available geological data, and may thus help to refine age estimates. Such evolutionary data may also help unravel potential biotic and abiotic factors that promote speciation events. Here, mitochondrial sequencing data of one of the largest groups of endemic taxa in the Ohrid watershed, the leech genus Dina, is used to test whether it represents an ancient lake species flock, to study the role of potential horizontal and vertical barriers in the watershed for evolutionary events, to estimate the onset of diversification in this group based on molecular clock analyses, and to compare this data with data from other endemic species for providing an approximate time frame for the origin of Lake Ohrid. Based on the criteria speciosity, monophyly and endemicity, it can be concluded that Dina spp. from the Ohrid watershed, indeed, represents an ancient lake species flock. Lineage sorting of its species, however, does not seem to be complete and/or hybridization may occur. Analyses of population structures of Dina spp. in the Ohrid watershed indicate a horizontal zonation of haplotypes from spring and lake populations, corroborating the role of lake-side springs, particularly the southern feeder springs, for evolutionary processes in endemic Ohrid taxa. Vertical differentiation of lake taxa, however, appears to be limited, though differences between populations from the littoral and the profundal are apparent. Molecular clock analyses indicate that the most recent common ancestor of extant species of this flock is approximately 1.99 ± 0.83 million years (Ma) old, whereas the split of the Ohrid Dina flock from a potential sister taxon outside the lake is estimated at 8.30 ± 3.60 Ma. Comparisons with other groups of endemic Ohrid species indicated that in all cases, diversification within the watershed started ≤2 Ma ago. Thus, this estimate may provide information on a minimum age for the origin of Lake Ohrid. Maximum ages are less consistent and generally less reliable. But cautiously, a maximum age of 3 Ma is suggested. Interestingly, this time frame of approximately 2–3 Ma ago for the origin of Lake Ohrid, generated based on genetic data, well fits the time frame most often used in the literature by geologists.

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Effects of human settlement and roads on diel activity patterns of elephants (Loxodonta africana )

African Journal of Ecology ◽

10.1111/aje.12552 ◽

2018 ◽

Vol 56 (4) ◽

pp. 872-881 ◽

Cited By ~ 8

Author(s):

Kaitlyn M. Gaynor ◽

Paola S. Branco ◽

Ryan A. Long ◽

Dominique D. Gonçalves ◽

Petter K. Granli ◽

...

Keyword(s):

Activity Patterns ◽

Loxodonta Africana ◽

Diel Activity ◽

Human Settlement ◽

Diel Activity Patterns

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Activity patterns of the small and medium felid (Mammalia: Carnivora: Felidae) guild in northeastern India

Journal of Threatened Taxa ◽

10.11609/jott.4662.11.4.13432-13447 ◽

2019 ◽

Vol 11 (4) ◽

pp. 13432-13447 ◽

Cited By ~ 3

Author(s):

Shomita Mukherjee ◽

Priya Singh ◽

André Pinto Silva ◽

Chandan Ri ◽

Kashmira Kakati ◽

...

Keyword(s):

Activity Patterns ◽

Regional Scale ◽

Diel Activity ◽

Point Scale ◽

Clouded Leopard ◽

Northeastern India ◽

Additional Information ◽

Extant Species ◽

Diel Activity Patterns ◽

Leopard Cat

Fifteen extant species of cats inhabit India, and the northeastern region of the country is among the richest with nine species. Among these are the “standard four”, an assemblage of Clouded Leopard Neofelis nebulosa, Asiatic Golden Cat Catopuma temminckii, Marbled Cat Pardofelis marmorata, and Leopard Cat Prionailurus bengalensis, which also occur across southeastern Asia. Within India, despite several surveys in this region, very little information exists on the ecology of this assemblage to explain their co-occurrence. In this paper, we put together data from several independent camera trapping studies over 10 sites across northeastern India to examine and interpret diel activity patterns of this group. While we present results for all the four species, we focus on two species, the Marbled Cat and Leopard Cat, which are of very similar body size and are potential competitors. We used kernel density estimates to measure diel activity patterns of all four species and overlap in activity between Marbled Cat and Leopard Cat at the regional scale as well as the point scale. We obtained 783 captures of the standard four from >27,500 trap nights. The Asiatic Golden Cat and Marbled Cat were strongly diurnal, Clouded Leopard largely crepuscular and nocturnal, and Leopard Cat largely nocturnal. The degree of overlap between Marbled Cat and Leopard Cat activity was low and in consensus with other studies across southeastern Asia. We interpret this as the differing niche spaces of the two cats due to their specific pre-existing adaptations, not restricted to the effects of competition. The point scale analysis when both cats are captured at the same location and separately show no shift in activity pattern, supporting our hypothesis of pre-existing differences in resources, such as food, playing a major role in facilitating co-existence. Our study, however, is preliminary and additional information with robust analysis is required to test this finding.

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Ontogeny of the diel activity patterns in relation to downstream dispersal in riverine cyprinid fishes

Journal of Fish Biology ◽

10.1111/j.1095-8649.2003.216bk.x ◽

2003 ◽

Vol 63 ◽

pp. 254-254

Author(s):

M. Ondračková ◽

E. Mazurová ◽

M. Reichard ◽

P. Jurajda

Keyword(s):

Activity Patterns ◽

Diel Activity ◽

Diel Activity Patterns ◽

Cyprinid Fishes

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Non-uniform evolutionary response of gecko eye size to changes in diel activity patterns

Biology Letters ◽

10.1098/rsbl.2018.0064 ◽

2018 ◽

Vol 14 (5) ◽

pp. 20180064 ◽

Cited By ~ 10

Author(s):

Lars Schmitz ◽

Timothy E. Higham

Keyword(s):

Phenotypic Diversity ◽

Activity Patterns ◽

Model Fitting ◽

Regime Shifts ◽

Least Square ◽

Diel Activity ◽

Relevant Variable ◽

Eye Size ◽

Evolutionary Response ◽

Diel Activity Patterns

Geckos feature a large range of eye sizes, but what drives this phenotypic diversity is currently unknown. Earlier studies point towards diel activity patterns (DAPs) and locomotory mode, but phylogenetic comparative studies in support of the proposed adaptive mode of eye evolution are lacking. Here, we test the hypothesis of DAPs as the driver of eye size evolution with a dataset on 99 species of gecko. Results from phylogenetic generalized least-square analysis (PGLS) and multivariate model-fitting reveal smaller eyes in diurnal geckos consistent with different phenotypic optima. However, Bayesian analyses of selective regime shifts demonstrate that only two of nine transitions from nocturnal to diurnal activity are coupled with decreases in eye size, and two other regime shifts are not associated with DAP transitions. This non-uniform evolutionary response suggests that eye size is not the only functionally relevant variable. Evolutionary adaptations may therefore include different combinations of several traits (e.g. photoreceptors), all with the same functional outcome. Our results further demonstrate that DAP only partially explains eye size diversity in geckos. As open habitats favour the evolution of large eyes while obstructed habitats favour small eyes, the degree of habitat clutter emerges as another potential axis of eye diversification.

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Testing the spatial and temporal framework of speciation in an ancient lake species flock: the leech genus <i>Dina</i> (Hirudinea: Erpobdellidae) in Lake Ohrid

Biogeosciences Discussions ◽

10.5194/bgd-7-5011-2010 ◽

2010 ◽

Vol 7 (4) ◽

pp. 5011-5045 ◽

Cited By ~ 6

Author(s):

S. Trajanovski ◽

C. Albrecht ◽

K. Schreiber ◽

R. Schultheiß ◽

T. Stadler ◽

...

Keyword(s):

Molecular Clock ◽

Abiotic Factors ◽

Time Frame ◽

Recent Common Ancestor ◽

Species Flock ◽

Ancient Lake ◽

Lake Ohrid ◽

Most Recent Common Ancestor ◽

Extant Species

Abstract. Ancient Lake Ohrid on the Balkan Peninsula is considered to be the oldest ancient lake in Europe with a suggested Plio-Pleistocene age. Its exact geological age, however, remains unknown. Therefore, molecular clock data of Lake Ohrid biota may serve as an independent constraint of available geological data, and may thus also help to refine age estimates. Such evolutionary data may also help unravel potential biotic and abiotic factors that promote speciation events. Here, mitochondrial sequencing data of one of the largest groups of endemic taxa in Lake Ohrid, the leech genus Dina, is used to test whether it represents an ancient lake species flock, to study the role of horizontal and vertical barriers in Lake Ohrid for evolutionary events, to estimate the onset of intralacustrine diversification in this group based on molecular clock analyses, and to compare this data with data from other endemic species for providing an approximate time frame for the origin of Lake Ohrid. Based on the criteria speciosity, monophyly and endemicity, it can be concluded that Lake Ohrid Dina, indeed, represents an ancient lake species flock. Lineage sorting of its species, however, does not seem to be complete. Analyses of population structures of Dina spp. in the Ohrid watershed indicate a horizontal zonation of haplotypes from spring and lake populations, corroborating the role of lake-side springs, particularly the southern feeder springs, for evolutionary processes in endemic Ohrid taxa. Vertical differentiation of lake taxa, however, appears to be limited, though differences between populations from the littoral and the profundal are apparent. Molecular clock analyses indicate that the most recent common ancestor of extant species of this flock is approximately 1.99±0.83 Ma old, whereas the split of the Lake Ohrid Dina flock from a potential sister taxon outside the lake is estimated at 8.30±3.60 Ma. Comparisons with other groups of endemic Ohrid species indicated that in all cases, intralacustrine diversification started ≤2 Ma ago. Thus, this estimate may provide information on a minimum age for the origin of Lake Ohrid. Maximum ages are less consistent and generally less reliable. But cautiously, a maximum age of 3 Ma is suggested. Interestingly, this time frame of approximately 2–3 Ma for the origin of Lake Ohrid, generated based solely on evolutionary data, well fits the time frame most often used in the literature by geologists. Future studies must show whether this concurrence holds true.

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