Max Ringler

Max Ringler
University of California, Los Angeles | UCLA · Department of Ecology and Evolutionary Biology

27.64
 · 
PhD
About
75
Research items
5,600
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489
Citations
Introduction
Max Ringler currently works at the Department of Ecology and Evolutionary Biology, University of California, Los Angeles. Max does research in behavioural ecology, tropical ecology, and herpetology with a special focus on bioacoustics and GIS methods. Their current projects are 'Social structures in amphibians – communication networks (CN) and social networks (SN) in the Neotropical frog Allobates femoralis.' and 'Movement ecology and spatial cognition of tropical amphibians'.
Research Experience
Jan 2011
University of Vienna
Position
  • PostDoc Position
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Projects
Projects (3)
Project
The La Gamba Field Station is a research and teaching facility of the University of Vienna, situated at the edge of the Piedras Blancas National Park in SW Costa Rica. Being located in one of the most species-rich lowland rainforests in Central America, it is an ideal location for field research, courses and seminars. The field station plays a significant role in research into tropical rainforests, raises awareness for rainforest conservation and research, and provides an opportunity for students and anyone interested in the natural world to increase their knowledge of rainforests.
Project
We investigate how the combination of environmental factors, reproductive strategies, and navigational abilities result in similarities and differences of tropical frog spatial behavior. Going beyond descriptive science, we attempt to link individual movements to cognitive abilities and environmental factors through experimental manipulations and individual tracking in the field.
Project
Amphibians are generally considered as the vertebrate taxon with the least complex social structures, despite their diverse social behaviours. This is mainly attributed to their brains, which are often seen as too small and too simply structured to provide the neural complexity that is considered a prerequisite for so called ‘higher’ social cognition. Nevertheless, increasing evidence has been found for social structuring in certain amphibian taxa, mainly in the context of communication and mating networks. Dendrobatid frogs provide several characteristics such as prolonged breeding, stable territorial systems, prominent acoustic communication, acoustic ranging and parental care, which predestines this taxon as an excellent candidate for studies on social complexity in amphibians. I hypothesize that certain amphibians indeed feature long-lasting social structures and aim to investigate this phenomenon in a captive colony and a semi-natural, island population of the Dendrobatid frog Allobates femoralis. This species has become a model species for anuran behavioural ecology and communication over the last decade. To explore and quantify communication- and social networks I will use social network analysis, the state-of-the-art approach to assess social structures in animals. Data collection will be mainly conducted via microphone arrays, both in the laboratory and in the field. While for the captive population I will use a conventional wired array, for the field study I will use a state-of-the-art wireless microphone array with sound source localization and automated acoustic caller identification. This approach of ‘reality mining’ will allow me to collect continuous data on calling activity and calling interactions in the captive and the wild population. In the field, the automated acoustic sampling will be accompanied by extensive behavioural observations and genetic sampling of the studied individuals and their offspring. In an initial, explorative phase, I want to search for patterns and the prevalence of structures in the communication- and social network of the captive and the wild population. For the wild population, I then want to relate individual social network metrics with reproductive output to assess the influence of the social network position on individual reproductive success. The proposed project addresses two currently urged requests: (1) it provides a new model species to study the evolution of social complexity in the root taxon of terrestrial vertebrates, and (2) it will use a state-of-the art sensor network to continuously monitor calling activity in the communication- and social network of an anuran population. The project will be conducted in collaboration with (1) Daniel Blumstein, (2) Peter Narins, and (3) Charles Taylor at the Department of Ecology and Evolutionary Biology (EEB) at the University of California, Los Angeles (UCLA), thereby bringing together three of the world’s leading researchers on social network analysis (1), anuran communication (2), and distributed sensor networks (3).
Research
Research items (75)
Article
Full-text available
Social complexity arises from the formation of social relationships like social bonds and dominance hierarchies. In turn, these aspects may be affected by the degree of fission-fusion dynamics, i.e., changes in group size and composition over time. Whilst fission-fusion dynamics has been studied in mammals, birds have received comparably little att...
Article
Full-text available
Some territorial animals recognize familiar neighbours and are less aggressive to established neighbours than they are to strangers. This form of social recognition produces a ‘dear enemy’ effect, which may allow animals to reduce the costs of territory defence. The dear enemy effect is thought to reflect either the decreased threat posed by neighb...
Answer
With Amphibians and IR measurements/imagery one thing you also need to consider is that moist skin, like with photo cameras will give you all sorts of reflections, also in the IR part of the spectrum, and especially under varying, natural illumination conditions. So to make meaningful measurements of (small) frog surfaces, unless it is a mostly dry skinned species, you will have to somehow overshadow the frog to make sure it is actual IR emission,and not IR reflections from the sun that you are measuring. Of course this then comes with severe constraints in terms of not disturbing frogs and is also the reason why we mostly switched to measure substrate surface temperatures of perches immediately after the frog moved away. But of course I understand there are circumstances where the actual surface temperature of the frog can be of interest!
Best
Max
Answer
Hi Philippe,
as these devices use (infread) light through special optics, the problem is mainly a physical one. Think of you request as the analogue to a telephoto-lens which should give you maximum magnification (small spot size) over maximum distance (minimal disturbance). With photo cameras, such lenses get huge and very expensive pretty quick, and such is the case with IR thermometers. Now FLIR cameras do nothing but replacing the single temperature sensor with a 2-dimensional image chip that can detect IR, analogous to the chip in a photo camera. Then detection area theoretically is limited by the pixel size, however, as each pixel is considerably smaller as the sensor of a IR meter, also accuracy will be reduced, as less photons will be received per sensor site/pixel, and you will end up with noise the smaller the pixels (sensor).
What is the exact purpose of your measurements? As you emphasize minimal disturbance I assume you want to measure body temperature of frogs that are resting or calling on a substrate for a while already (not moving, and you don't want to scare them away). As poikolotherms, the frogs will, by and large, have the same temperature as their substrate unless two things are the case - 1. either they are capable to produce some heat internally, or 2. they have (considerably large) different heat absorbance characteristics than the substrate they are sitting on, causing them to heat up either more or less then then substrate.
To detect this latter case of frogs having a body temperature which deviates considerably from their substrate temperature, you still can make differential measurements, (mostly) regardless of the spot size of your IR meter - so male one measurement with the frog covering as much as possible of the spot, and one of the substrate directly beside the frog. However, as I said the effect you want to measure has to be quite strong, as also the accuracy of IR thermometers in the price range you specified is mostly within 0.5-1 °C (although they give readings at0.1 °C).
So long story short, unless the purpose of your study is to measure (tiny) temperature difference across (within) the surface of a frog, and with the money you state you have available, you will be fine with IR thermometers with a spot size within 1-3 times the SUL of the frogs you want to measure.These devices mostly have optics with a distance to spot ratio of 20:1 - so at 20 cm distance your spot size is 1 cm in diameter, at 40 cm its 2, ... at 1 m its 5 cm and so on. Also they often are available at different calibration qualities (accuracies) which problaby should be of equal, if not even more concern as the spot size.
Hope these ideas help a little
Max
Article
Full-text available
Parental decisions in animals are often context‐dependent and shaped by fitness trade‐offs between parents and offspring. For example, the selection of breeding habitats can considerably impact the fitness of both offspring and parents, and therefore parents should carefully weigh the costs and benefits of available options for their current and fu...
Answer
Oriana (https://www.kovcomp.co.uk/oriana/), a stat program specialised on circular statistics, has a 30-day free trial. PAST (https://folk.uio.no/ohammer/past/) has some circular stats functionality. And in R you have the 'circular' package: https://cran.r-project.org/web/packages/circular/
Cheers Max
P.S.: Check you g-mailbox ;-)
Article
Full-text available
Animals relying on uncertain, ephemeral and patchy resources have to regularly update their information about profitable sites. For many tropical amphibians, widespread, scattered breeding pools constitute such fluctuating resources. Among tropical amphibians, poison frogs (Dendrobatidae) exhibit some of the most complex spatial and parental behavi...
Data
Movement speed during tadpole transport Histogram showing the range of movement speed during tadpole transport from one tracking location to the next one (m/h).
Data
Tagged male tadpole carrier The tag consists of a silicon tube around the waist, with an additional silicone strap between the hind legs, a small diode (beneath the white sealing) and a dipole antenna made of flexible coated wire.
Data
Movement precision during tadpole transport Summarized data of the average angular deviation, average distance from the straight-line path and SC for the tadpole transport of frogs which encountered only available pools during tadpole transport (A) and frogs which encountered non-available pools (N), minimum, maximum, 1st and 3rd quartile, median a...
Data
Movement precision during homing Summarized data of the average angular deviation, average distance from the straight-line path and SC for the homing trajectories of frogs which encountered only available pools during tadpole transport (A) and frogs which encountered non-available pools (N), minimum, maximum, 1st and 3rd quartile, median and mean.
Data
Homing trajectories Trajectory map showing movement patterns of frogs homing back to their territory after tadpole transport. Red asterisks represent the territory centers of tracked carriers and colored lines show different tracking events. Squares represent the cross-array of thirteen artificial tadpole deposition sites, blue squares representing...
Data
Summarized results of homing trajectories Each row represents a specific tracking event. Columns show the tracked distance during homing, straight line distance (from the last deposition site to the territory center), duration of homing, whether homing took more than one day (overnight = 1), average speed and the straightness coefficient.
Data
Movement speed during homing Histogram showing the range of movement speed during homing from one tracking location to the next one (m/h).
Data
Model results—Influence of weather on movement speed File contains Table S1 on model selection, Table S2 showing all model-averaged coefficients and the discussion of the model results.
Data
Summarized results of tadpole transport trajectories Each row represents a specific tracking event. Columns show the frog ID, number of tadpoles, tracked distance, total time of the tracked path (h), average speed (m/h) across the entire TTs, number of deposition sites visited (in parentheses the number of available (a) and non-available (n) deposi...
Article
Full-text available
Acoustic ranging allows identifying the distance of a sound source and mediates inter-individual spacing and aggression in territorial species. Birds and mammals are known to use more complex cues than only sound pressure level (SPL), which can be influenced by the signaller and signal transmission in non-predictable ways and thus is not reliable b...
Answer
Hi Kirsten, we have used Genoscreen and Ecogenics for our microsats so far and were very satisfied with them - they have a stepwise pricing system, allowing you to get products at every stage of the process, so for example, you could get the full library they can obtain, and then do the polymorphy check for yourself.
Article
Full-text available
Systematic infanticide of unrelated young has been reported in several animal taxa. Particular attention has been given to carnivores and primates, where infanticide is a sexually selected strategy of males to gain increased access to female mating partners. Cannibals must ensure avoiding their own offspring and targeting only unrelated young. Ther...
Article
Full-text available
Acoustic species recognition in anurans depends on spectral and temporal characteristics of the advertisement call. the recognition space of a species is shaped by the likelihood of heterospecific acoustic interference. the dendrobatid frogs Allobates talamancae (cOpe, 1875) and Silverstoneia flotator (dunn, 1931) occur syntopi-cally in southwest c...
Answer
Hi Gregor,
Sorry for the late reply, the email you used is not my most recent one and hardly checked. I agree with L. savagei, which basically is the split-off and newly described northern form of L. pentadactylus.
For the second picture S. sordida seems to be not a too bad guess - night colouration, as they look strikingly different during the day, and can also be highly variable. This is mainly based on proportions and shape of the snout and estimated size (as far as this is possible from the leaf). However, I have no identification literature available right now, and one would probably need more information (location, time, call) or even the specimen at hand for a good identification. I am not an expert on the Costa Rican herpetofauna, and the booklet from 2004 is mainly based on the book of Savage - I am more familiar with the Guiana Shield and Northern Brazil.
Best
Max
Data
Video S1: Crows' responses to the tonic immobility test.
Data
Figure S1: Sketch of the zoo of Vienna (‘Tiergarten Schönbrunn’). Figure S2: Division of the zoo into an evenly spaced hexagonal grid (grid sites) used to assess space use of crows. Figure S3: Maps generated in QGIS, to identify the number of foraging sites (a) and grid sites (b) individual crows were sighted in, respectively. Table S1: Frequenc...
Article
Full-text available
While personality-dependent dispersal is well studied, local space use has received surprisingly little attention in this context, despite the multiple consequences on survival and fitness. Regarding the coping style of individuals , recent studies on personality-dependent space use within a habitat indicate that 'proactive' individuals are wider r...
Article
Full-text available
The ability to associate environmental cues with valuable resources strongly increases the chances of finding them again, and thus memory often guides animal movement. For example, many temperate region amphibians show strong breeding site fidelity and will return to the same areas even after the ponds have been destroyed. In contrast, many tropica...
Article
Full-text available
The ability to differentiate between one's own and foreign offspring ensures the exclusive allocation of costly parental care to only related progeny. The selective pressure to evolve offspring discrimination strategies is largely shaped by the likelihood and costs of offspring confusion. We hypothesize that males and females with different reprodu...
Article
Full-text available
Reproductive skew, the uneven distribution of reproductive success among individuals, is a common feature of many animal populations. Several scenarios have been proposed to favour either high or low levels of reproductive skew. Particularly a male-biased operational sex ratio and the asynchronous arrival of females is expected to cause high variat...
Article
Full-text available
Parental care systems are shaped by costs and benefits to each sex of investing into current versus future progeny. Flexible compensatory parental care is mainly known in biparental species, particularly where parental desertion or reduction of care by 1 parent is common. The other parent can then compensate this loss by either switching parental r...
Article
Full-text available
Spreading reproduction across time or space can optimize fitness by minimizing the risks for offspring survival in varying and unpredictable environments. Poison frogs (Dendrobatidae) are characterized by complex spatial and reproductive behaviour, such as territoriality, prolonged courtship and parental care. The partitioning of larvae from terres...
Article
Full-text available
“Ecosystem engineering” describes habitat alteration by an organism that affects another organism; such nontrophic interactions between organisms are a current focus in ecological research. Our study quantifies the actual impact an ecosystem engineer can have on another species by using a previously identified model system—peccaries and rainforest...
Answer
Wild-ID, which is around since ~2010, should work with the patterns of your frogs. We use it successfully with the dorsal patterns of Fire Salamanders (Salamandra salamandra) and the ventral patters of poison frogs (Allobates femoralis).
Article
Full-text available
For animals with spatially complex behaviours at relatively small scales, the resolution of a global positioning system (GPS) receiver location is often below the resolution needed to correctly map animals’ spatial behaviour. Natural conditions such as canopy cover, canyons or clouds can further degrade GPS receiver reception. Here we present a det...
Article
Full-text available
Reliably marking larvae and re-identifying them after metamorphosis is a challenge that has hampered studies on recruitment, dispersal, migration, and survivorship of amphibians for a long time, since conventional tags are not reliably retained through metamorphosis. Molecular methods allow unique genetic fingerprints to be established for individu...
Article
Full-text available
Among vertebrates, comparable spatial learning abilities have been found in birds, mammals, turtles and fishes, but virtually nothing is known about such abilities in amphibians. Overall, amphibians are the most sedentary vertebrates, but poison frogs (Dendrobatidae) routinely shuttle tadpoles from terrestrial territories to dispersed aquatic depos...
Article
Full-text available
Here we document the development of thirteen novel microsatellite markers for the reticulated glass frog Hyalinobatrachium valerioi (Centrolenidae). Nine of those markers were polymorphic and contained between 4 and 34 alleles per locus (mean = 20.3) in 138 individuals (91 males, 47 females) from the field site 'La Gamba', Costa Rica. Average obser...
Article
Full-text available
Introduction The ability to relocate home or breeding sites after experimental removal has been observed in several amphibians and the sensory basis of this behavior has been studied in some temperate-region species. However, the actual return trajectories have rarely been quantified in these studies and it remains unknown how different cues guide...
Article
Full-text available
In anurans, vocalization is the most prominent form of communication. Unique acoustic properties are used to enable species discrimination and to avoid mismating. Syntopic, vocally co-active frog species differentiate each other acoustically by using advertisement calls with different temporal and spectral properties. In territorial frogs, playback...
Article
Full-text available
Individuals should aim to adjust their parental behaviours in order to maximize the success of their offspring but minimize associated costs. Plasticity in parental care is well documented from various bird, mammal and fish species, whereas amphibians were traditionally assumed as being highly instinct-bound. Therefore, little is known about 'highe...
Article
Full-text available
Here we document the development of seven novel polymorphic microsatellite markers for the brilliantthighed poison frog Allobates femoralis (Dendrobatidae). We found between six and 27 alleles per locus in 100 individuals (50 males, 50 females) from the field site ‘Saut Pararé’, French Guiana, with an average observed heterozygosity of 0.79. One lo...
Article
Full-text available
Dendrobatidae (dart-poison frogs) exhibit some of the most complex spa-tial behaviors among amphibians, such as territoriality and tadpole trans-port from terrestrial clutches to widely distributed deposition sites. In species that exhibit long-term territoriality, high homing performance after tadpole transport can be assumed, but experimental evi...
Article
Full-text available
The adaptive significance of sequential polyandry is a challenging question in evolutionary and behavioral biology. Costs and benefits of different mating patterns are shaped by the spatial distribution of individuals and by genetic parameters such as the pairwise relatedness between potential mating partners. Thus, females should become less choos...
Article
Full-text available
While field and laboratory based studies have provided significant insights into the parental care and courtship behaviour of dendrobatoid frogs, a comprehensive assessment of their genetic mating systems and population genetic parameters has been precluded because of the lack of highly variable DNA markers. Here we document the development of nine...
Data
Average values of the different area estimators for point of the central area. A) ellipse, B) star, C) triangle, D) angle, E) circle, F) irregular; area is given in arbitrary units. (TIF)
Data
Example for the HRT-LSCV estimator. 95% (black area) and 50%-isoclines (grey area) of the HRT-LSCV estimator of the irregular virtual territory with increasing numbers of equiangular trials, based on all equiangular subsets that include the trials towards direction 0°. (TIF)
Data
Average values of the different area estimators for equiangular trial-subsets in virtual territories. A) ellipse, B) star, C) triangle, D) angle, E) circle, F) irregular; horizontal grey line indicates ‘true’ absolute territory size; area in arbitrary units. (TIF)
Data
Rank order of 15 territories as evaluated by the LoCoH, DH, and STC estimator. (TIF)
Data
Example for the detailed hull estimator. Detailed hull of the Central points (grey area) and outer points (black area) of the irregular virtual territory with increasing numbers of equiangular trials, based on all equiangular subsets that include the trials towards direction 0°. (TIF)
Data
Example of the LoCoH estimator. LoCoH of the irregular virtual territory with increasing numbers of equiangular trials, based on all equiangular subsets that include the trials towards direction 0°; areas of stepwise increasing 5% isoclines in incremental shades of grey. (TIF)
Article
Full-text available
Territoriality is a widespread behaviour in animals and its analysis is crucial in several areas of behavioural, ecological and evolutionary research. Commonly, territory size is assessed through territory mapping and the application of simple area estimators such as minimum convex polygons. In the present study we demonstrate that territory size c...
Article
Full-text available
Our knowledge about genetic mating systems and the underlying causes for and consequences of variation in reproductive success has substantially improved in recent years. When linked to longitudinal population studies, cross-generational pedigrees across wild populations can help answer a wide suite of questions in ecology and evolutionary biology....