Vertical Rock Surfaces Research Articles

Mechanical loading of primate fingers on vertical rock surfaces

Mechanical loading of finger bones (phalanges) can induce angular curvature, which benefits arboreal primates by dissipating forces and economising the recruitment of muscles during climbing. The recent discovery of extremely curved phalanges in a hominin, Homo naledi, is puzzling, for it suggests life in an arboreal milieu, or, alternatively, habitual climbing on vertical rock surfaces. The importance of climbing rock walls is attested by several populations of baboons, one of which uses a 7-m vertical surface to enter and exit Dronkvlei Cave, De Hoop Nature Reserve, South Africa. This rock surface is an attractive model for estimating the probability of extreme mechanical loading on the phalanges of rock-climbing primates. Here we use three-dimensional photogrammetry to show that 82–91% of the climbable surface would generate high forces on the flexor tendon pulley system and severely load the phalanges of baboons and H. naledi. If such proportions are representative of vertical rock surfaces elsewhere, it may be sufficient to induce stress-mitigating curvature in the phalanges of primates.Significance: We present the first three-dimensional photogrammetric analysis of a vertical rock surface climbed by a non-human primate, the chacma baboon (Papio ursinus). Our results show that a large proportion of a vertical rock wall would compel crimp and slope hand positions during climbing – grips that could explain the extraordinary phalangeal curvature expressed by a Middle Pleistocene hominin, Homo naledi.

Does the common topknot Zeugopterus punctatus (Teleosteii: Pleuronectiformes: Scophthalmidae) use a novel Venturi-effect attachment mechanism? A testable hypothesis.

Common topknots (Zeugopterus punctatus) attach to vertical rock surfaces and overhangs. It has been speculated that attachment is by a suction cup, with the median (anal, dorsal) fins providing a peripheral seal. Here the authors propose that the attachment is actually based on a Venturi effect. The rear portions of the median fins continually move in a fan-like fashion (at c. 4cycles per second). This movement produces a tailward fluid flow that ventilates the shallow underbody space between the fish and its rocky substratum. The anterior portions of the median fins seal the space laterally, but the space is open anterior (beneath the raised head) and posterior to the sea. The mid-underbody space likely has a lower cross-sectional area than does the front intake or rear exit, so flow should be faster (and pressure lower) within it than outside, thus providing pressure gradient suction. Topknots attach to rough and heavily biofouled surfaces, presumably because the high numbers of fin rays and their associated membranes plus fine muscle control allow effective sealing. The attachment ability is shared by all members of the flatfish tribe Phrynorhombini; it can be related to anatomical peculiarities and constitutes a probable synapomorphy for this clade.

Life History of Western Ghats endemic and threatened Anuran – Matheran leaping frog, (Indirana leithii) with notes on its feeding preferences

ABSTRACTThe species Indirana leithii (Anura: Ranixalidae) is endemic to the northern Western Ghats of India and is distributed between latitudes 16°N and 21°N in this region. The tadpoles of this species have been previously studied for their morphology and feeding behaviour; however, their natural history is still not completely understood. In the current study, we provide information about the mating behaviour, egg laying and metamorphosis of the species. We observed that the species possesses reproductive mode number 19 as these frogs lay eggs inside the natural cavities of vertical rock surfaces near streams and waterfalls and their tadpoles are adapted for adhering to the wet rock surface, where they feed on algae (including diatoms) growing in seepage on the rocks. Interestingly, there is no audible calling or territory guarding involved during the courtship behaviour. This has been observed for the first time in any Indian anuran. We also provide data on food preferences of adults and tadpoles.

Limnophyes guarani sp. n., a new hygropetric Orthocladiinae from southern Brazil (Diptera: Chironomidae).

A new species of Limnophyes Eaton collected in the Corvo Branco Mountains in Santa Catarina State is described and figured, based on male and female adults, larva and pupa. The species groups with L. griseata (Edwards) and L. bidumus Sæther as the adults have a pronounced humeral pit with lanceolate setae and an additional group of lanceolate setae just posterior to antepronotum. The adults are, however, distinctly smaller, have a lower AR and have more lanceolate setae in the group just posterior to antepronotum than the two other species. The pupa can easily be separated from the pupa of L. bidumus as the anal macroseta is longer than the anal lobe. The larva lives hygropetric on vertical rock surfaces. A key to male adults of Neotropical Limnophyes is given.

Using biomimetic loggers to measure interspecific and microhabitat variation in body temperatures of rocky intertidal invertebrates

Until recently, marine scientists have relied heavily on satellite sea surface temperatures and terrestrial weather stations as indicators of the way in which the thermal environment, and hence the body temperatures of organisms, vary over spatial and temporal scales. We designed biomimetic temperature loggers for three species of rocky intertidal invertebrates to determine whether mimic body temperatures differ from the external environment and among species and microhabitats. For all three species, microhabitat temperatures were considerably higher than the body temperatures, with differences as great as 11.1°C on horizontal rocky substrata. Across microhabitats, daily maximal temperatures of the limpet Cellana tramoserica were on average 2.1 and 3.1°C higher than body temperatures of the whelk Dicathais orbita and the barnacle Tesseropora rosea respectively. Among-microhabitat variation in each species’ temperature was equally as variable as differences among species within microhabitats. Daily maximal body temperatures of barnacles placed on southerly facing vertical rock surfaces were on average 2.4°C cooler than those on horizontal rock. Likewise, daily maximal body temperatures of whelks were on average 3.1°C cooler within shallow rock pools than on horizontal rock. Our results provide new evidence that unique thermal properties and microhabitat preferences may be important determinants of species’ capacity to cope with climate change.

Descriptions of Immature Stages of Three Species of Laccocorinae (Hemiptera: Heteroptera: Naucoridae) from India

Abstract Adults and first through fifth instars of three species of Naucoridae in the subfamily Laccocorinae were collected from localities in Tamil Nadu and Karnataka states in southern India. Specifically, Heleocoris indicus (Montandon) and Heleocoris vicinus (Montandon) were collected from the vegetated margins of streams that contained no congeners. Pogonocaudina indica Sites & Zettel was collected from vertical rock surfaces at the type locality. All instars of these three species are described here. First instars of both species of Heleocoris are immaculate, whereas subsequent instars are densely punctate. The first instar of P. indica has pronounced dorsal tubercles with stout spines, whereas subsequent instars lack these structures. All instars of P. indica have a deep terminal cleft and dense fringe of hairs on the perimeter of the posterior abdominal segments. Second through fifth instars of these three species can be distinguished based on relative length of the mesonotal wing pad compared with the exposed part of the metanotal lateral margin.

Establishment and persistence of species-rich patches in a species-poor landscape: role of a structure-forming subtidal barnacle

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 380:187-198 (2009) - DOI: https://doi.org/10.3354/meps07905 Establishment and persistence of species-rich patches in a species-poor landscape: role of a structure-forming subtidal barnacle A. R. Davis*, D. W. Ward Institute for Conservation Biology and School of Biological Sciences, University of Wollongong, New South Wales 2522, Australia *Email: adavis@uow.edu.au ABSTRACT: Some sessile invertebrates are capable of maintaining space in barren habitats produced by sea urchins, thereby creating species-rich patches in a species-poor landscape. We sought to determine the role of a large and common barnacle, Austrobalanus imperator, in the establishment and persistence of these species-rich patches. Barnacle density was modified in 2 experiments at sites in southeastern Australia. The first experiment concerned community establishment and involved the addition of barnacles in 4 densities (zero [control], low, medium and high) to plots on vertical rock surfaces. The addition of barnacles at ecologically realistic densities and spatial arrangements rapidly resulted in statistically significant increases in invertebrate cover and diversity. After 56 mo, the diversity of invertebrates was significantly higher on plots that received high densities of barnacles relative to controls. However, invertebrate cover no longer differed between treatment plots, despite evidence that barnacles modify the grazing intensity of sea urchins. The second experiment assessed the persistence of sessile invertebrates following the removal of barnacles from well-established assemblages dominated by sponges. The removal of barnacles did not hinder the rapid recovery of sponges to pre-manipulation levels, indicating that barnacles played an inconsequential role in well-established assemblages. We conclude that barnacles play an important functional role in this system, as they promote the recruitment of sessile invertebrates. It was also clear that the development of invertebrate assemblages on natural vertical surfaces was very slow, which raises the question of whether we are examining these important occupiers of space at appropriate temporal and spatial scales. KEY WORDS: Cirripedia · Echinoidea · Grazing activity · Habitat structure · Porifera · Sessile invertebrates · Structural heterogeneity · Rocky subtidal zone Full text in pdf format PreviousNextCite this article as: Davis AR, Ward DW (2009) Establishment and persistence of species-rich patches in a species-poor landscape: role of a structure-forming subtidal barnacle. Mar Ecol Prog Ser 380:187-198. https://doi.org/10.3354/meps07905 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 380. Online publication date: April 07, 2009 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2009 Inter-Research.

A PHYLOGENETIC TEST FOR ADAPTIVE CONVERGENCE IN ROCK-DWELLING LIZARDS

Phenotypic similarity of species occupying similar habitats has long been taken as strong evidence of adaptation, but this approach implicitly assumes that similarity is evolutionarily derived. However, even derived similarities may not represent convergent adaptation if the similarities did not evolve as a result of the same selection pressures; an alternative possibility is that the similar features evolved for different reasons, but subsequently allowed the species to occupy the same habitat, in which case the convergent evolution of the same feature by species occupying similar habitats would be the result of exaptation. Many lizard lineages have evolved to occupy vertical rock surfaces, a habitat that places strong functional and ecological demands on lizards. We examined four clades in which species that use vertical rock surfaces exhibit long hindlimbs and flattened bodies. Morphological change on the phylogenetic branches leading to the rock-dwelling species in the four clades differed from change on other branches of the phylogeny; evolutionary transitions to rock-dwelling generally were associated with increases in limb length and decreases in head depth. Examination of particular characters revealed several different patterns of evolutionary change. Rock-dwelling lizards exhibited similarities in head depth as a result of both adaptation and exaptation. Moreover, even though rock-dwelling species generally had longer limbs than their close relatives, clade-level differences in limb length led to an overall lack of difference between rock- and non-rock-dwelling lizards. These results indicate that evolutionary change in the same direction in independent lineages does not necessarily produce convergence, and that the existence of similar advantageous structures among species independently occupying the same environment may not indicate adaptation.

A review of Eotrechus Kirkaldy (Hemiptera: Heteroptera: Gerridae) of Thailand with descriptions of three new species

Three new species of Eotrechus Kirkaldy were collected from vertical rock surfaces of waterfalls in northern and central Thailand. Eotrechus siamensis sp. n. was collected at Doi Inthanon and Doi Suthep National Parks in Chiang Mai Province, northern Thailand. Eotrechus elongatus sp. n. and Eotrechus romglao sp. n. were collected from waterfalls in Phu Hin Rongkla National Park in Phetchabun Province, central Thailand. These new species are described and illustrated here as is the female of Eotrechus petraeus Andersen. In addition, Eotrechus kalidasa Kirkaldy was discovered for the first time in Thailand. Finally, diagnostic and distributional information of all known species of this genus in Thailand are given.

Electrical Resistance Sensors Record Spring Flow Timing, Grand Canyon, Arizona

Springs along the south rim of the Grand Canyon, Arizona, are important ecological and cultural resources in Grand Canyon National Park and are discharge points for regional and local aquifers of the Coconino Plateau. This study evaluated the applicability of electrical resistance (ER) sensors for measuring diffuse, low-stage (<1.0 cm) intermittent and ephemeral flow in the steep, rocky spring-fed tributaries of the south rim. ER sensors were used to conduct a baseline survey of spring flow timing at eight sites in three spring-fed tributaries in Grand Canyon. Sensors were attached to a nearly vertical rock wall at a spring outlet and were installed in alluvial and bedrock channels. Spring flow timing data inferred by the ER sensors were consistent with observations during site visits, with flow events recorded with collocated streamflow gauging stations and with local precipitation gauges. ER sensors were able to distinguish the presence of flow along nearly vertical rock surfaces with flow depths between 0.3 and 1.0 cm. Laboratory experiments confirmed the ability of the sensors to monitor the timing of diffuse flow on impervious surfaces. A comparison of flow patterns along the stream reaches and at springs identified the timing and location of perennial and intermittent flow, and periods of increased evapotranspiration.

A revision of the African hygropetric genus Coelometopon Janssens, and description of Oomtelecopon new genus (Coleoptera: Hydraenidae)

The African hygropetric beetle genus Coelometopon Janssens is revised, and Oomtelecopon new genus is described, based on the study of 1,884 specimens. The genus Coelometopon is redescribed, and redescriptions are provided for C. cavifrons Janssens, C. leleupi Janssens, C. madidum Janssens, and C. mussardi Janssens. Eighteen new species of Coelometopon and two new species of Oomtelecopon are described. The two genera are placed in the Coelometoponini, new tribe, of the subfamily Prosthetopinae. A key to the two genera and 24 known species is given. High resolution digital images of all holotypes are presented (online version in color), the male genitalia are illustrated, and geographic distributions are mapped. Structural details of a representative species, C. granulatum, are illustrated with scanning electron micrographs. Members of Coelometopon are restricted to hygropetric microhabitats, being found on vertical or near vertical rock surfaces which have a thin film of flowing water, such as rock seeps and splash zones of waterfalls and cascades. Members of Oomtelecopon have been collected from algae in seeps, from wet cliff faces, and by sifting marsh shore litter. New species of Coelometopon are: C. angulatum (Lesotho: Mamathes, 5 mi. E. Tayateyaneng), C. balfourbrownei (South Africa: Cape Prov., George District, near George), C. blinkwater (South Africa: Cape Prov., Table Mountain, Blinkwater ravine), C. brincki (Lesotho: Mamathes, 5 mi. E. Tayateyaneng), C. clandestinum (South Africa: Natal Prov., Olivershoek Pass), C. coronatum (Lesotho: Mamathes, 5 mi. E. Tayateyaneng), C. costatum (South Africa: Transvaal Prov., Zoutpansberg, 6 mi. NNE Louis Trichardt), C. drakensbergense (South Africa: Natal Prov., Drakensburg, Cathedral Peak, Mikes Pass), C. emarginatum (South Africa: Transvaal Prov., Nelshoogte, Knuckles rocks forest), C. endroedyi (South Africa: Natal Prov., Drakensburg, Loteni Reserve), C. fimbriatum (South Africa: Cape Prov., Swellendam District, Langeberge Mountains, Tradouw Pass), C. granulatum (South Africa: Natal Prov., Mpumalanga, 13 km E Sabie), C. kilimanjaro (Tanzania: Kilimanjaro, Marangu), C. langebergense (South Africa: Cape Prov., Swellendam District, Langeberge Mountains, Tradouw Pass), C. minipunctum (South Africa: Natal Prov., Drakensberg, Cathedral Peak, Rainbow G.), C. natalensis (South Africa: Natal Prov., Mpumalanga, 28 km N Graskop), C. punctipennis (South Africa: Cape Prov., Xalanga District, Cala Pass), and C. zulu (South Africa: Natal Prov., Zulu Drakensberg, 7 km N Nogome Forest Reserve). New species of Oomtelecopon are: O. sebastiani (South Africa: Cape Prov., Cape-Cederberg), and O. setosum (type species) (South Africa: Cape Prov., Table Mountain, Blinkwater Ravine).

Movement and orientation patterns in the commercial sea cucumberParastichopus californicus(Stimpson) (Holothuroidea: Aspidochirotida)

The commercial sea cucumber Parastichopus californicus was tagged in situ, and its daily summer activity patterns followed over periods of up to two months. On bedrock covered with shell rubble, cobbles, and boulders, P. californicus crawled an average of 3.9 m/d. Long term movement on gently sloping substrata showed no directional bias. Tidal currents in the study areas had no influence upon either orientation or locomotory direction. On vertical rock surfaces, P. californicus has a negative geotropic orientation which we conclude is associated with opportunistic suspension feeding. On horizontal substrata, feeding and locomotory behaviour in P. californicus are simultaneous activities, and we suggest that the apparent random activity patterns in these sea cucumbers is mediated by an evenly distributed and renewable source of detrital food.

SETTLEMENT AND METAMORPHOSIS OF A TEMPERATE SOFT-CORAL LARVA (ALCYONIUM SIDERIUMVERRILL): INDUCTION BY CRUSTOSE ALGAE

The temperate soft-coral Alcyonium siderium Verrill has a demersal planula larva which usually settles and metamorphoses on vertical rock surfaces near the parent colony. Such surfaces are covered by a variety of encrusting invertebrate species and by three common crustose algae (Lithothamnium glaciale, Phymatolithon rugolosum, and Waernia mirabilis). Larvae settle and metamorphose most frequently on these three algal species in the field (Sebens, 1983). Contact with each of the three crustose algae induced settlement and metamorphosis within 1-5 days in laboratory experiments. Rock or shell fragments, even with naturally filmed surfaces, did not induce metamorphosis in the same time period. A few larvae did metamorphose on the rock, shell, and glass or plastic surfaces of the containers, taking up to 30 days to do so. Larvae were kept alive up to 194 days but their competence to metamorphose declined significantly after ten days. The half-life of larvae that did not metamorphose was approximately 25 days. Larvae presented with coralline algae in darkness delayed metamorphosis by approximately 10-20 days, but most of them did metamorphose by 30 days. Neither sea water incubated with coralline algae, nor coralline algae in close proximity (4-5 mm) to the larvae, but without contact, induced metamorphosis. Induction of settlement and metamorphosis is thus mediated by surface contact with the algae and probably not by a dissolved chemical. Presence of the colonial ascidian, Aplidium pallidum, inhibited metamorphosis even when larvae were able to contact coralline algae, and also caused early larval death.

Papers from the Echinoderm Conference. 11. A stable system of predation on a holothurian by four asteroids and their top predator

Seven species of asteroids feed on Cucumaria lubrica, but together they harvest only 3% of the population or 10% of the standing crop biomass per year at the locality of the study. The rates of predation by the asteroid Solaster dawsoni on the predators of C. lubrica are high enough and the rates of growth and successful recruitment into the area by the predators of C. lubrica are low enough to indicate that [he predators of C. lubrica are possibly kept low in abundance by the higher predator Solaster dawsoni. Solaster stimpsoni, the most abundant predator of C. lubrica in the area, has a behavioural escape mechanism which becomes increasingly effective as S. stimpsoni grows large and when it is on vertical rock surfaces. While S. dawsoni removes about 24–32% of the S. stimpsoni population each year, probably preventing a buildup in numbers, the refuge in size of a reproductive stock allows the persistence of the long-lived, slow-growing, S. stimpsoni. Dermasterias, a predator of C. lubrica with a refuge in size but with no behavioural escape mechanism to S. dawsoni, is 0.07 times as common as S. stimpsoni with a size-frequency distribution represented predominantly by large adults. Solaster endeca and Leptasterias, predators of C. lubrica with no known refuge to S. dawsoni, are 0.004 and 0.008 times as common as S. stimpsoni and may be considered strays from other habitats. No significant changes in abundance were observed in the 3 trophic levels of the association from 1965 to 1976: C. iubrica, 4400 m-2; S. stimpsoni, 0.5 m-2; S. dawsoni, 0.007 m-2. The stability of the system results from different control mechanisms and refuges at each trophic level.

Notonemouridae of Australia (Plecoptera, Ins.)

AbstractA revision of the Australian and Tasmanian members of the family Notonemouridae is given, studying the abundant material from several Australian and European collections and additional material obtained during the author's collecting trip to Australia and Tasmania in 1966. The family of Notonemouridae was hitherto only poorly known from this area (6 species). The following text gives descriptions of 16 species, 10 of them, and 4 genera, being new to science. The larvae of this family in Australia and Tasmania live in cold springs and rivers, especially on seepage areas in high mountains, where they climb on vertical rock surfaces; the adults are able to jump by means of their hind femora.

New Distributional Records of Breeding Mexican Ducks

significance of notching. The variation among species in the presence of notched toes might be associated with differences in mechanisms of climbing. That some climbing species (e.g., Sitta carolinensis) lack notches is not surprising in view of the diversity of specializations for climbing in birds. Comparable is the occurrence of stiffened tail feathers in some but not all climbers. Undoubtedly, notching evolved independently in different lineages. It can thus illustrate convergent evolution, such as between the Old World Wall Creeper (Tichodroma) and the New World Canyon Wren (Catherpes), both specialized for feeding on vertical rock surfaces. The similar notching of Tichodroma and Certhia may also be due to convergence, for Tichodroma is reported to be more clo ely r lated to Sitta than to Certhia (Vaurie, Amer. Mus. Novitates, 1854:1-26, 1957; Lbhrl, J. Ornithol., 105:153-181, 1964). As m st examined species lack notches, and there is no evidence that species with notches are primitive, the occurrence of notching is probably a derived, rather than primitive, condition within both the order Passeriformes and the suborder Oscines. The following have generously provided access to specimens: N. P. Ashmole (Yale Peabody Museum), E. R. Blake (Field Museum), S. M. Russell (University of Arizona). Miss Mary Hubbard prepared figure 1.

Petroglyphs of California and Adjoining States

THIS publication is issued by the Department of Anthropology of the University of California. It contains much that is of great interest to the student of primitive art, for it is concerned with a quantity of drawings which occur throughout California, being mostly executed on vertical rock-surfaces. There are both carvings and paintings, consisting for the most part of highly conventionalised figures of men and animals as well as what can only be classed as geometric patterns, and the whole forms a most interesting art group. University of California Publications in American Archœology and Ethnology. Vol. 24, No. 2: Petroglyphs of California and adjoining States. By Julian H. Steward. Pp. 47 - 238 + plates 22–94. (Berkeley: University of California Press; London: Cambridge University Press, 1929.) 2.50 dollars.