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New species of Rhabdosynochus Mizelle and Blatz 1941 (Monogenoidea: Diplectanidae) from the gills of centropomid fishes (Teleostei) off the Pacific coast of Mexico

Smithsonian Libraries
In the course of the investigations into the fish parasites in the Tres Palos Lagoon in the State of Guerrero off the Pacific coast of Mexico, the following diplectanid species (Monogenoidea) from the gills of centropomids were found: Rhabdosynochus alterinstitus n. sp. from Centropomus nigrescens; Rhabdosynochus lituparvus n. sp., Rhabdosynochus volucris n. sp., and Rhabdosynochus siliquaus n. sp. from Centropomus robalito (Centropomidae). The apparent synapomorphic character supporting a sister relationship of these diplectanids is a single, sheathlike accessory piece comprising 3 distal branches of the male copulatory organ. The origin of the present diplectanid on centropomids is discussed, and it is suggested that this may be the result of allopatric speciation as a result of the uplift of the Panamanian Isthmus, thereby separating the Pacific and Atlantic Oceans during Pleistocene (3-5 million yr ago).

Out of Amazonia again and again: episodic crossing of the Andes promotes diversification in a lowland forest flycatcher

Smithsonian Libraries
Most Neotropical lowland forest taxa occur exclusively on one side of the Andes despite the availability of appropriate habitat on both sides. Almost all molecular phylogenies and phylogenetic analyses of species assemblages (i.e. area cladograms) have supported the hypothesis that Andean uplift during the Late Pliocene created a vicariant barrier affecting lowland lineages in the region. However, a few widespread plant and animal species occurring in lowland forests on both sides of the Andes challenge the generality of this hypothesis. To understand the role of the Andes in the history of such organisms, we reconstructed the phylogeographic history of a widespread Neotropical flycatcher (Mionectes oleagineus) in the context of the other four species in the genus. A molecular phylogeny based on nuclear and mitochondrial sequences unambiguously showed an early basal split between montane and lowland Mionectes. The phylogeographic reconstruction of lowland taxa revealed a complex history, with multiple cases in which geographically proximate populations do not represent sister lineages. Specifically, three populations of M. oleagineus west of the Andes do not comprise a monophyletic clade; instead, each represents an independent lineage with origins east of the Andes. Divergence time estimates suggest that at least two cross-Andean dispersal events post-date Andean uplift.

Interspecific variation in primary seed dispersal in a tropical forest

Smithsonian Libraries
Summary 1. We investigated the relationships of seed size, dispersal mode and other species characteristics to interspecific variation in mean primary seed dispersal distances, mean annual seed production per unit basal area, and clumping of seed deposition among 41 tropical tree species on Barro Colorado Island, Panama. 2. A hierarchical Bayesian model incorporating interannual variation in seed production was used to estimate seed dispersal, seed production, and clumping of seed rain for each species from 19 years of data for 188 seed traps on a 50-ha plot in which all adult trees were censused every 5 years. 3. Seed dispersal was modelled as a two-dimensional Student's T distribution with the degrees of freedom parameter fixed at 3, interannual variation in seed production per basal area was modelled as a lognormal, and the clumping of seed rain around its expected value was modelled as a negative binomial distribution. 4. There was wide variation in seed dispersal distances among species sharing the same mode of seed dispersal. Seed dispersal mode did not explain significant variation in seed dispersal distances, but did explain significant variation in clumping: animal-dispersed species showed higher clumping of seed deposition. 5. Among nine wind-dispersed species, the combination of diaspore terminal velocity, tree height and wind speed in the season of peak dispersal explained 40% of variation in dispersal distances. Among 31 animal-dispersed species, 20% of interspecific variation in dispersal distances was explained by seed mass (a negative effect) and tree height (a positive effect). 6. Among all species, seed mass, tree height and dispersal syndrome explained 28% of the variation in mean dispersal distance and seed mass alone explained 45% of the variation in estimated seed production per basal area. 7. Synthesis. There is wide variation in patterns of primary seed rain among tropical tree species. Substantial proportions of interspecific variation in seed production, seed dispersal distances, and clumping of seed deposition are explained by relatively easily measured plant traits, especially dispersal mode, seed mass, and tree height. This provides hope for trait-based generalization and modelling of seed dispersal in tropical forests.

The influence of canopy traits on throughfall and stemflow in five tropical trees growing in a Panamanian plantation

Smithsonian Libraries
Tree canopies partition rainfall into temporary canopy storage, throughfall and stemflow. Knowledge of this partitioning process is needed to predict the hydrological effects of the large areas of tree plantations that are being established in the tropics. In this study, we compared throughfall, stemflow and interception in four Neotropical and one exotic tree species growing in selection trials in the Republic of Panama. We sought to answer four questions: (1) Are there interspecific differences in total throughfall and stemflow, and throughfall and stemflow for a range of rainfall depths?, (2) How do crown traits influence interspecific differences in throughfall?, (3) Does the spatial heterogeneity of throughfall differ among species? and (4) How do species affect litter biomass and other variables that influence rainfall erosivity? Rainfall depth mediated interspecific differences in throughfall and stemflow, the relative importance of crown traits in the interception process, and spatial heterogeneity of throughfall. Total throughfall was between 10.9 and 16.2% less in Acacia mangium than Gliricidia sepium, Guazuma ulmifolia, Ochroma pyramidale or Pachira quinata. Increasing rainfall also changed relative quantities of throughfall and stemflow among species. For example, throughfall was similar in Gliricidia and Acacia for small rain events, but increased more rapidly in Gliricidia with increasing rainfall depth. Interspecific differences in throughfall were driven, in part, by canopy traits. Leaf area index (LAI), crown depth and crown openness all affected throughfall from smaller storms, but live crown length was the only significant predictor of throughfall in storms that were deeper than 20 mm. The spatial heterogeneity of throughfall beneath individual tree canopies increased with rainfall depth, but was always lower in Gliricidia than in Acacia, Ochroma, or Pachira. High litter biomass and cover in Acacia and Ochroma relative to other species would be likely to buffer the erosive effects of raindrop impacts. These complex interactions between rainfall and species traits may affect local hydrology, and may need to be explicitly considered in reforestation projects in the seasonal tropics.

Historical biogeography and speciation in the reef fish genus Haemulon (Teleostei: Haemulidae)

Smithsonian Libraries
The high biodiversity of tropical marine hotspots has long intrigued evolutionary biologists and biogeographers. The genus Haemulon (grunts) is one of the most important (numerically, ecologically, and economically) reef fish groups in the New World and an excellent candidate to test hypotheses of speciation and diversity generation in the Greater Caribbean, the richest Atlantic biodiversity hotspot, as well as the eastern Pacific. To elucidate the phylogenetic relationships among the species of Haemulon, we obtained a combined total of 2639 base pairs from two mitochondrial genes (cytochrome b and cytochrome oxidase I), and two nuclear genes (TMO-4C4 and RAG2) from all nominal species. Parsimony, Maximum likelihood, and Bayesian analyses resulted in a well-resolved phylogeny with almost identical topologies. Previous phylogenetic hypotheses based on adult morphology, such as the close relationship among H. aurolineatum, H. boschmae, and H. striatum were not supported, whereas others using developmental characters, such as the relationship between H. plumieri and H. sciurus, were confirmed. Our data also indicate that the populations of the nominal H. steindachneri from the two sides of the Isthmus of Panama are genetically divergent at the species level in each ocean, and that the boga, Inermia vittata (family Inermiidae), belongs in the genus Haemulon. This evidence implies that there are 21 valid species of Haemulon, two more than previously recognized. The Amazon barrier and the Isthmus of Panama seem to have played roles in allopatric speciation of Haemulon. However, the majority of sister species pairs have completely overlapping distributions, indicating that vicariance is not the only process driving speciation in this genus. We conclude that both vicariance between biogeographic provinces, and ecological mechanisms of speciation within provinces contribute to species richness in the genus Haemulon.

Body size shapes caste expression, and cleptoparasitism reduces body size in the facultatively eusocial bees Megalopta (Hymenoptera : Halictidae)

Smithsonian Libraries
We used the facultatively social sweat bee Megalopta genalis (Halictidae) to test whether body size is associated with social caste. Behavioral observations showed that non-reproductive foragers were significantly smaller than reproductive nest mate queens, and foragers were also smaller than presumed pre-dispersal reproductives. Moreover, among females from field-collected nests without behavioral observations, relative body size correlated with relative ovary size. Reproductive status is not a direct result of body size, as body size was not significantly associated with either ovary size or fecundity among both solitary and social reproductives. Reproductive status is apparently an outcome of social competition for reproductive dominance, and status is influenced by size relative to nest mates. Our study is the first to demonstrate an association of body size with caste expression in a facultatively social species with relatively weak seasonal constraints on independent nesting. Larvae of a parasitic fly (Fiebrigella sp., Chloropidae) consume pollen provisions stored in nest cells of M. genalis and M. ecuadoria. We tested whether fly parasitism of M. genalis reduces body size. Parasitized females are significantly smaller as adults than their unparasitized nestmates. This reduction is of a similar magnitude to the size differences between castes, and has the potential to shape host reproductive options by influencing competition with nest mates. We present data on the prevalence of parasitism from four collections of M. genalis and two collections of M. ecuadoria from Barro Colorado Island, Panama, and La Selva, Costa Rica.

Biology of a nocturnal bee, Megalopta atra (Hymenoptera: Halictidae; Augochlorini), from the Panamanian highlands

Smithsonian Libraries
Bees of the genus Megalopta have gained attention as a result of their social nesting and nocturnal foraging. Seventeen nests of Meglaopta atra from the highlands of Chiriqui Province, Panama, were collected at the end of the dry season when brood rearing is expected to be at its peak. Most nests contained single females; within multifemale nests only one female possessed enlarged ovarioles, although some non-reproductive individuals were inseminated. In two

Did tectonic activity stimulate oligo-Miocene speciation in the Indo-West Pacific?

Smithsonian Libraries
Analyses of molecular phylogenies of three unrelated tropical marine gastropod genera, Turbo, Echinolittorina, and Conus, reveal an increase in the rate of cladogenesis of some Indo-West Pacific (IWP) clades beginning in the Late Oligocene or Early Miocene between 23.7 and 21.0 million years ago. In all three genera, clades with an increased rate of diversification reach a maximum of diversity, in terms of species richness, in the central IWP. Congruence in both the geographical location and the narrow interval of timing suggests a common cause. The collision of the Australia and New Guinea plate with the southeast extremity of the Eurasian plate approximately 25 Mya resulted in geological changes to the central IWP, including an increase in shallow-water areas and length of coastline, and the creation of a mosaic of distinct habitats. This was followed by a period of rapid diversification of zooxanthellate corals between 20 and 25 Mya. The findings reported here provide the first molecular evidence from multiple groups that part of the present-day diversity of shallow-water gastropods in the IWP arose from a rapid pulse of speciation when new habitats became available in the Late Oligocene to Early Miocene. After the new habitats were filled, the rate of speciation likely decreased and this combined with high levels of extinction (in some groups), resulted in a slow down in the rate of diversification in the genera examined.

Kadua haupuensis (Rubiaceae: Spermacoceae), a new endemic species from Kaua'i, Hawaiian Islands

Smithsonian Libraries
Abstract The new species Kadua haupuensis is described and illustrated from the isolated Mt. Ha'upu region of Kaua'i, Hawaiian Islands. This new species belongs to Kadua subg. Kadua sect. Wiegmannia. It is characterized by a subdioecious (leaky dioecious) breeding system and appears most closely related to another apparently dioecious species endemic to Kaua'i, Kadua flynnii, with which it is compared. Although the only original wild population is critically endangered and may possibly be extinct, this new species has been successfully propagated and is currently secure in cultivation.

Marine Macroalgal Diversity Assessment of Saba Bank, Netherlands Antilles

Smithsonian Libraries
Background: Located in the Dutch Windward Islands, Saba Bank is a flat-topped seamount (20-45 m deep in the shallower regions). The primary goals of the survey were to improve knowledge of biodiversity for one of the world's most significant, but little-known, seamounts and to increase basic data and analyses to promote the development of an improved management plan. Methodology/Principal Findings: Our team of three divers used scuba to collect algal samples to depths of 50 m at 17 dive sites. Over 360 macrophyte specimens (12 putative new species) were collected, more than 1,000 photographs were taken in truly exceptional habitats, and three astonishing new seaweed community types were discovered. These included: (1) "Field of Greens'' (N 17 degrees 30.620', W 63 degrees 27.707') dominated by green seaweeds as well as some filamentous reds, (2) "Brown Town'' (N 17 degrees 28.027', W 63 degrees 14.944') dominated by large brown algae, and (3) "Seaweed City'' (N 17 degrees 26.485', W 63 degrees 16.850') with a diversity of spectacular fleshy red algae. Conclusions/Significance: Dives to 30 m in the more two-dimensional interior habitats revealed particularly robust specimens of algae typical of shallower seagrass beds, but here in the total absence of any seagrasses (seagrasses generally do not grow below 20 m). Our preliminary estimate of the number of total seaweed species on Saba Bank ranges from a minimum of 150 to 200. Few filamentous and thin sheet forms indicative of stressed or physically disturbed environments were observed. A more precise number still awaits further microscopic and molecular examinations in the laboratory. The expedition, while intensive, has only scratched the surface of this unique submerged seamount/atoll.

Oral history interview with Irving Marantz, 1968 August 31

Archives of American Art
1 sound file (50 min.); digital, wav

Transcript: 23 pages

An interview with Irving Marantz conducted 1968 August 31, by Dorothy Seckler, for the Archives of American Art.

Oral history interview with Virginia Cuthbert, 1995 August 28

Archives of American Art
1 sound cassette (90 min.) : analog.

Transcript: 40 pages

An interview of Virginia Cuthbert conducted 1995 August 28, by Robert F. Brown, for the Archives of American Art, in Cuthbert's home, Buffalo, New York.

Virginia Cuthbert discusses her family background in the Pittsburgh, Pennsylvania area; and her father's love of art and acquaintance with Homer Saint-Gaudens, Director of the Carnegie Museum of Art; her very early art education and, later, her study in Europe on a Syracuse University fellowship; her brief study with Felice Carena in Florence and critiques of her work in London by Augustus John and Colin Gill; her study and friendship in New York with George Luks and the beginning of a long friendship with the composer, Virgil Thompson; graduate study in fine arts at the University of Pittsburgh; her engagement to the future museum director, Andrew Ritchie, its breaking-off, and her marriage to Philip Elliott; her further study at the Carnegie Institute with Alexander Kostellow; and a sketching trip to France and Spain.

Oral history interview with John Coolidge, 1989 March 7-29

Archives of American Art
21 sound files : digital, wav file

Transcript: 148 pages

An interview with John Coolidge conducted 1989 March 7-29, by Robert F. Brown, for the Archives of American Art.

Interview with Ilya Bolotowsky

Archives of American Art
1 sound tape reel : analog ; 7 in. ; 1 hr., 17 min., 47 sec.

Bolotowsky is interviewed by Adelaide Freer, a student of Irving Sandler's. He discusses his association with the group called "The Ten Whitney Dissenters," his personal history, various styles of art, and his own work.

Report of the National Zoological Park Commission to the Senate and House of Representatives

Smithsonian Libraries
Cover title.

"Transmitted January 17, 1890."

Also available online.

NZP copy bound with Report of the Acting Manager of the National Zoological Park and succeeding title of the report as well as other material, barcode 39088017698358.

Elecresource

The Technologist

Smithsonian Libraries
Subtitle varies.

"A monthly record of science applied to art and manufacture."

Latest issue consulted: Vol. 7, no. [84] (July 1867) = n.s., no. [12].

Vol. 7, no. 73-[84] also called: New ser., no. 1-[12].

Also available online.

Elecresource

Day Without Art at Thirty

Cooper-Hewitt, National Design Museum
Image features a poster consisting of white text on a black background. Upper center: The words "VISUAL AIDS" are printed with a cracked effect. Columns of text appear on the bottom with the names of arts organizations. Above the columns, in slightly larger, bolder text: “A Day Without Art December 1, 1989 A national day of mourning and call for action in response to the AIDS / crisis involving individuals and organizations including the following:”. Please scroll down to read the blog post about this object.World AIDS Day (December 1), was designated in 1988 as an occasion to raise awareness of AIDS and to commemorate those lost to the disease. Developed by Visual AIDS, an organization that supports artists and communities affected by HIV and AIDS, this poster announces the first Day Without Art on December 1, 1989. Day Without...

Luce Unplugged: Five Questions for We Were Pirates

Smithsonian American Art Museum
Three views of Mike Boggs, lead singer ofAn interview with Mike Boggs of We Were Pirates, in advance of their Luce Unplugged appearance.

Luce Unplugged: FIVE QUESTIONS FOR Rob Stokes

Smithsonian American Art Museum
ThumbnailLuce interview with musician Rob Stokes on his art and inspiration.

Luce Unplugged: Five questions for OG Lullabies

Smithsonian American Art Museum
Thumbnail

Mercury-Laden Fog May Be Poisoning California’s Mountain Lions

Smithsonian Magazine

As fog drifts over the coast of California, it may carry a noxious substance that is endangering one of the region’s keystone species. A new study in Scientific Reports has found elevated levels of mercury in pumas that roam through the Santa Cruz Mountains—and researchers suspect that marine fog is responsible for wafting the neurotoxin into the terrestrial food chain.

Mercury is a naturally occurring element that is released into the environment through both natural processes and human activities, like mining and coal-fired power plants. Once mercury is in the atmosphere, it can rain down into the ocean, where anaerobic bacteria convert it into methylmercury—“the most toxic form of mercury,” according to the University of California, Santa Cruz. At high enough concentrations, methylmercury can cause neurological and reproductive damage, among other negative effects.

Some of the methylmercury in the ocean rises to the surface of the water, where it is carried inland by fog. "Fog is a stabilizing medium for methylmercury," explains Peter Weiss-Penzias, an environmental toxicologist at UC Santa Cruz and lead author of the new study. "Fog drifts inland and rains down in microdroplets, collecting on vegetation and dripping to the ground, where the slow process of bioaccumulation begins."

Mercury levels in fog are not high enough to pose a danger to humans. But land-dwelling organisms are at risk because as mercury moves up the food chain—from plants, to plant-eating animals, to carnivores—its concentrations can increase by 1,000 times.

For the new study, researchers sought to determine how an apex predator along the coast of California—a region that is likely to be swallowed up by marine fog—is being impacted by mercury in the atmosphere. The team focused on the Santa Cruz Mountains because this geographic area “form[s] an effective barrier to the inland penetration of marine fog,” as the study authors explain.

The researchers analyzed hair and whisker samples from 94 pumas that dwell along the coast and 18 pumas that occupy inland areas. The coastal mountain lions had higher concentrations of mercury in their biological samples, with an average of 1,500 parts per billion (ppb), compared to around 500 ppb in the inland puma samples. Two of the pumas displayed “sub-lethal” mercury levels that may have a negative impact on reproduction. One animal was contaminated with mercury levels known to be toxic to other species, like mink and otters. “It was found dead,” Weiss-Penzias tells Alani Letang of KSBW.

To trace the trickle-up effect of mercury in the environment, the researchers also looked at levels of the neurotoxin in both lichen and deer samples; deer eat lichen, and pumas eat deer, as Letang explains. Once again, concentrations were higher in samples from ocean facing sites, compared to those from inland sites. The presence of elevated mercury levels in the lichen was particularly telling because, as Weiss-Penzias explains, the organism does not have any roots—meaning that the contamination had to be coming from the atmosphere, rather than the ground.

As Alejandra Reyes-Velarde of the Los Angeles Times points out, the risk of fog-borne mercury poisoning is just one of several threats to pumas in California. Since 2002, five of the great cats have died after ingesting rat poison, which can be dangerous to pumas even if it does not kill them. Biologists suspect the toxic substance is making the animals vulnerable to mange, a potentially fatal skin disease. Roads and freeways fragment the animals’ habitat, leading to fatal vehicle collisions and creating barriers that force the cats to in-breed, reducing their genetic diversity.

“These mercury levels might compound the impacts of trying to make it in an environment like the Santa Cruz Mountains, where there is already so much human influence, but we don’t really know,” says Chris Wilmers, study co-author and director of the Puma Project. “Levels will be higher 100 years from now, when the Earth’s mercury budget is higher because of all the coal we’re pumping into the atmosphere.”

As apex predators, pumas play an important role in their ecosystem, helping control populations of large ungulates, like deer, as well as small predators. Any threats to the cats’ well-being also risk disrupting the delicate balance of their environment.

"We need to protect the top predators in the environment," says Weiss-Penzias. "They perform ecosystem services. When you change one thing, it has cascading effects through the system."

Is This Chess Piece Unearthed in Jordan the World's Oldest?

Smithsonian Magazine

Almost 30 years after its discovery, a small sandstone figurine unearthed in Jordan has been identified as perhaps the oldest chess piece discovered to date.

As John Oleson, a researcher at Canada’s University of Victoria, reported during the annual meeting of the American Schools of Oriental Research late last month, archaeologists found the carved piece of white sandstone while conducting excavations at Humayma, a former Islamic trading post in Jordan, in 1991.

Initially, Oleson writes in his presentation abstract, he and his colleagues thought the two-horned object, which measures less than an inch high, resembled an altar created by the Nabatean civilization. But after further examination, he is now convinced the carving is a “rook” or “castle” chess piece, as it closely resembles other ivory, stone and wooden rooks found at later sites in the Islamic world.

“This shape is standard for early Islamic pieces right through the 13th [or 14th] century,” Oleson tells Haaretzs Ariel David.

Per Science News’ Bruce Bower, the potential chess piece dates to between 680 and 749 A.D. At the time, the powerful Abbasid family owned and operated the Humayma trading outpost.

The rook’s discovery doesn’t change what researchers know about the origins of chess, but it does shed some light on how quickly the game gained traction and who exactly played it. David reports that chess was likely invented in India during the sixth century, spreading to Persia and throughout the Muslim world before eventually arriving in Europe.

The Humayma rook is carved of local sandstone, meaning the individual who owned it was likely not a social elite.

“In the literature, naturally they talk about the elites playing with chess pieces made of ivory, ebony, gold or rock crystal,” Oleson explains to David. “The world of low-class players doesn’t appear in that kind of literature so it’s good to have an archaeological record.”

According to the abstract, Humayma was a trading post located between Petra, capital of the Nabatean kingdom, and the Red Sea port of Aqaba on a trade route known as Via Nova Traiana.

Oleson writes, “Since the game probably was carried westward from India by the movement of merchants and diplomats, it is no surprise that early evidence for it should be found at a site on the busy Via Nova Traiana.”

The chess piece may boast ties to one of the most notable families in Islamic history. As David reports, Humayma was the hometown of the Abbasid clan, which overthrew the Ummayad caliphate in 750 and ruled much of the Islamic world until 1258 A.D.

While living in Humayma, the Abbasids kept tabs on events occurring in Syria and Iraq—including, in all likelihood, the emergence of a new game called chess.

“Early historians of the Abbasid family say the revolution was plotted in the little mosque next to the manor house,” says Oleson to David. “They talk about merchants coming around and giving information about events in Damascus and what the Umayyads were up to. So the Abbasids were in a place where they would have learned about chess fairly early on, fairly easily.”

Speaking with Bower of Science News, Oleson notes that chess quickly became “very popular in the early Islamic world,” serving as a pastime that helped bridge differences between the rich and the poor, as well as Muslims and Christians.

The two-pronged Humayma rook’s abstract shape is a variation on the chess piece’s initial form: a chariot pulled by two horses. Per Haaretz, the rook’s appearance shifted upon its arrival in the Islamic world, which prohibited the use of figurative images, but the piece retained its original name—rukh, or “chariot” in Persian. When Europeans adopted the game centuries later, players interpreted the prongs as masonry work on forts or towers, and so the rook became the castle seen today.

Given the fact that archaeologists don’t know exactly when the sandstone rook was created, other specimens recovered may have a better claim to the title of “oldest known chess piece.”

A set of figurines found in Uzbekistan in 1977 dates to around 700 A.D., for example, and in 2002, archaeologists in Albania unveiled a sixth-century ivory piece unearthed in a Byzantine palace. The figure resembles a modern chess piece, complete with a cross on top, and would predate the widely accepted arrival of chess in Europe by 700 years. Critics, however, point out that chess was likely not even invented at this point in history.

Oleson tells David there are probably older chess pieces out there still waiting to be found. After all, the strategic showdown was invented at least a century before an early chess aficionado carved the Humayama rook.

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