South American woodpeckers, new study


Dryocopus galeatus (left) appears remarkably similar to Dryocopus lineatus erythrops (center) and Campephilus robustus (right), but it's only a distant relative. Credit K. Zimmer and R.J. Moller

From the Central Ornithology Publication Office:

11 August 2015

Deceptive woodpecker uses mimicry to avoid competition

Birds of a feather may flock together, but that doesn’t mean they share a genetic background. Though birds were first classified into groups primarily based on appearance, research forthcoming in The Auk: Ornithological Advances by Brett Benz of the American Museum of Natural History, Mark Robbins of the University of Kansas Biodiversity Institute, and Kevin Zimmer of the Los Angeles County Museum of Natural History demonstrates that this method isn’t necessarily accurate: in a group of very similar-looking South American woodpecker species, genetic analysis has now shown one to be only a distant cousin of the others, in an intriguing case of visual mimicry. By copying the appearance of larger, socially dominant woodpecker species, it reduces the aggression and competitive interference that it receives from them and has more access to food resources as a result.

The most familiar type of mimicry typically involves warning or “aposematic” coloration, in which a harmless species apes the color patterns of a dangerous or unappealing one to avoid predators; a famous instance is the Viceroy butterfly, which shares the striking colors of the more noxious Monarch. By contrast, the Helmeted Woodpecker (Dryocopus galeatus) represents an example of a different and less well understood form of mimicry, known as interspecific social dominance mimicry or ISDM.

The shy and little-known species shares the red crest, black back, and barred underside of two larger woodpeckers Dryocopus lineatus and Campephilus robustus, all of which occupy the same habitat and share similar food preferences. The Helmeted Woodpecker’s similarity in appearance makes the larger, more dominant woodpecker species less likely to attack it, due to the costs of aggression between members of the same species. Though they had been previously classified in Dryocopus due to the remarkable similarities in their appearance, genetic analysis by Benz and his colleagues suggests that the Helmeted Woodpecker is actually not closely related to other Dryocopus woodpeckers at all and belongs in a different genus, Celeus. An independent group of researchers using the same data recently reported similar results in a paper published in the Journal of Ornithology.

“Co-author Mark Robbins and I had just finished a phylogenetic study examining species limits and vocalizations in Celeus woodpeckers when Mark, who was attending a meeting in Brazil, had the opportunity to observe a Helmeted Woodpecker at Intervales State Park,” according to Benz. “Upon hearing the bird vocalize, Mark was stunned that its call sounded nothing like Neotropical Dryocopus, and immediately knew we needed to examine its taxonomic status in the context of our recent Celeus study given that the Helmeted Woodpecker calls were most similar to several other Celeus species. Upon returning from Brazil, Mark consulted with co-author Kevin Zimmer, who had independently arrived at the same conclusions about the Helmeted Woodpecker belonging with Celeus, based on his behavioral observations spanning 20 years of fieldwork in Brazil.” As Benz puts it, “The Helmeted Woodpecker is basically a typical Celeus in Dryocopus clothing.”

“After several decades working on the discovery of the avian Tree of Life, it is still amazing what we are discovering! Reconstructing the phylogeny of these woodpeckers has corrected a century-old classification mistake, but more interestingly, it has revealed an unexpected new example of avian mimicry,” adds Richard Prum of Yale University, one of the originators of the ISDM hypothesis. “It has only recently been appreciated that small species may benefit from deceptively mimicking larger species to protect themselves from aggressive attack. This is similar to how a 12-year-old kid walking home from school will look and act tough to try to prevent himself from being harassed by older, bigger kids.”

Relatively little is known about the ecology and natural history of the Helmeted Woodpecker, which is found in Brazil, Paraguay, and Argentina, but it has experienced dramatic population declines and vanished from much of its former range due to deforestation. Hopefully, this new discovery about its evolutionary relationships and visual deception may increase interest in the species, as it provides an opportunity for scientists to further test predictions associated with ISDM. Ultimately, bringing the Helmeted Woodpecker’s sneaky strategy into the light may be what saves it from oblivion.

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“Phylogenetic relationships of the Helmeted Woodpecker (Dryocopus galeatus): A case of interspecific mimicry?” will be published on September 30, 2015, and will be available here</a; a pre-print version is available here.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists’ Union. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.

Frog discoveries, new species, poison


This video is called BBC: Poison Dart FrogsWild Caribbean.

From daily The Guardian in Britain:

Ribbiting news: frogs’ poison spines revealed and new species discovered

In two separate breakthroughs, a new species of tree frog has been discovered, while two species of Amazonian frog have been revealed to be venomous

Many of world’s frogs may be at risk of extinction, but something new always hops up in the amphibian world. In two separate journals in one afternoon, scientists have identified a brand new tree frog species high in the Peruvian cloud forest, while on the other side of the Andes, a biologist in the Amazon basin discovered the hard way the secret of survival of two familiar species: they are venomous.

The deadly duo – formally named Corythomantis greeningi and Aparasphenodon brunoi – are not just poisonous in the way made notorious by the poison dart frogs known as Dendrobatidae, which are the ones that indigenous Amerindians traditionally used to poison their blow darts. They are poisonous in the sense that they can inject a toxin from a sharp spine on their heads.

The poison is more deadly than the secretions of a pit viper, and one of the discoverers, Carlos Jared of the Instituto Butantan in Sao Paulo found out the hard way. While collecting C. greeningi he got a spine in his hand: intense, radiating pain followed for the next five hours.

The experience immediately explained why no hungry hunters are known to dine off either kind of frog. “This action would be even more effective on the mouth lining of an attacking predator,” said Dr Jared. As he and his research colleague Edmund Brodie of Utah State University tell the story in the journal Current Biology, it may have been a lucky strike. They calculate that one gram of toxin from the other, even more poisonous species, would be enough to kill 300,000 mice, or about 80 humans.

“It is unlikely that a frog of this species produces this much toxin, and only very small amounts would be transferred by the spines into a wound,” said Brodie. “Regardless, we have been unwilling to test this by allowing a frog to jab us with its spines.”

Meanwhile, 2350 metres high in the forests of the Peruvian Andes, biologists found a tiny fleshbelly frog hardly bigger than a beetle and hitherto unknown to science that had been leaping around in the leaf litter under their feet. The frog has been named Noblella madreselva (which means “mother jungle” in Spanish), in the journal Zookeys by its discoverers Allessandro Catenazzi of Southern Illinois University and Dr Vanessa Uscapi.

It announced itself by its striking colouration: a wide white mark on a black background, stretching from chest to belly, with a brown splash on its head that looks like a dark facial mask. The frog may have escaped notice until now, but it may survive only in that location, and in parts of the forest not yet logged. So it could be at high risk of hopping away to extinction. Half of all the world’s toads, frogs, newts and salamanders are in decline, and one third are at risk of extinction.

“It is therefore imperative to document the highly endemic amphibian faunas of the wet montane Andean forests as a first step towards designing a network of natural reserves that maximises protection of amphibian diversity,” the authors say.

See also here.

Urban birds conference, Leicester, England, April 2016


This 2015 video is called Watching Some Urban Birds in South America.

From the British Ornithologists’ Union:

5 – 7 April 2016 next BOU Conference

#BOU2016 | Urban Birds: pressures, processes and consequences

Leicester, UK

BOU 2016 Annual Conference

University of Leicester, UK

Follow on social media #BOU2016

View outline programme here

Conference theme

Urban development is one of the most transformative human land uses. It already dominates much of the globe, and urban areas will continue to expand rapidly, including in biodiversity hotspots. This poses enormous challenges to biodiversity conservation and urban planning. Urbanisation simultaneously provides opportunities for researchers to understand how species cope with, and adapt to, extreme and often novel selection pressures including habitat loss and fragmentation, pollution (noise, heat, light and chemical), altered biotic interactions (with pathogens, predators and prey) and interactions with people. Understanding how wildlife responds to urban life has become a global research priority, and ornithology is at the forefront of this research frontier.

This conference will bring together ornithologists, conservation biologists, evolutionary ecologists, and behavioural ecologists from academic and NGO sectors to showcase the latest developments in urban avian research and conservation.

The conference will cover a diverse range of topics including the following:

Urban bird monitoring and population trends;
Mechanisms structuring urban bird communities;
The demography of urban birds;
Gene flow, population sources and sinks
Urban pressures and avian adaptation;
Behavioural, physiological and evolutionary processes;
Human-avian interactions;
Future perspectives for managing urban landscapes.

The conference will be international in scope and is aimed at researchers and students, conservation organisations, statutory government agencies and those engaged in policy, advocacy and conservation management. It will provide opportunities to share high quality science, network and discuss new ideas. Whilst the conference focuses on avian research and conservation, much of the discussion will be relevant to participants whose core interest concerns taxonomic groups other than birds.

Blackpoll warbler migration in America, new research


This video from New York City says about itself:

Several male blackpoll warblers (Setophaga striata) are shown in Central Park on their migration to their northern breeding grounds. The blackpoll warbler spends the winter in northern South America and migrates to Alaska, Canada, and small portions of the northeastern United States to breed. It is a common species, and it is assessed as being of least concern by the IUCN Red List of Threatened Species.

This video was recorded on May 13, 14, and 17, 2014 in Central Park, New York City.

From Science Daily:

Tiny songbird discovered to migrate non-stop, 1,500 miles over the Atlantic

Date: March 31, 2015

Source: University of Massachusetts at Amherst

Summary: For the first time biologists report ‘irrefutable evidence’ that tiny blackpoll warblers complete a nonstop flight from about 1,410 to 1,721 miles (2,270 to 2,770 km) in just two to three days. For this work the scientists fitted geolocator packs on 20 birds in Vermont and 20 more in Nova Scotia. They were able to recapture three birds from the Vermont group and two from the Nova Scotia group for analyses.

For more than 50 years, scientists had tantalizing clues suggesting that a tiny, boreal forest songbird known as the blackpoll warbler departs each fall from New England and eastern Canada to migrate nonstop in a direct line over the Atlantic Ocean toward South America, but proof was hard to come by.

Now, for the first time an international team of biologists report “irrefutable evidence” that the birds complete a nonstop flight ranging from about 1,410 to 1,721 miles (2,270 to 2,770 km) in just two to three days, making landfall somewhere in Puerto Rico, Cuba and the islands known as the Greater Antilles, from there going on to northern Venezuela and Columbia. Details of their study, which used light-level, or solar, geolocators, appear in the current issue of Biology Letters.

First author Bill DeLuca, an environmental conservation research fellow at the University of Massachusetts Amherst, with colleagues at the University of Guelph, Ontario, the Vermont Center for Ecostudies and other institutions, says, “For small songbirds, we are only just now beginning to understand the migratory routes that connect temperate breeding grounds to tropical wintering areas. We’re really excited to report that this is one of the longest nonstop overwater flights ever recorded for a songbird, and finally confirms what has long been believed to be one of the most extraordinary migratory feats on the planet.”

While other birds, such as albatrosses, sandpipers and gulls are known for trans-oceanic flights, the blackpoll warbler is a forest dweller that migrates boldly where few of its relatives dare to travel. Most migratory songbirds that winter in South America take a less risky, continental route south through Mexico and Central America, the authors note. A water landing would be fatal to a warbler.

In the recent past, DeLuca explains, geolocators have been too large and heavy for use in studying songbird migration and the tiny blackpoll warbler, at around half an ounce (12 grams) or about as much as 12 business cards, was too small to carry even the smallest of traditional tracking instruments. Scientists had only ground observations and radar as tools.

But with recent advances in geolocator technology, they have become lighter and smaller. For this work, the researchers harnessed miniaturized geolocators about the size of a dime and weighing only 0.5g to the birds’ lower backs like a tiny backpack. By retrieving these when the warblers returned to Canada and Vermont the following spring, then analyzing the data, DeLuca and colleagues could trace their migration routes.

For this work the scientists fitted geolocator packs on 20 birds in Vermont and 20 more in Nova Scotia. They were able to recapture three birds from the Vermont group and two from the Nova Scotia group for analyses.

So-called light-level geolocators use solar geolocation, a method used for centuries by mariners and explorers. It is based on the fact that day length varies with latitude while time of solar noon varies with longitude. So all the instrument needs to do is record the date and length of daylight, from which daily locations can then be inferred once the geolocator is recaptured. “When we accessed the locators, we saw the blackpolls’ journey was indeed directly over the Atlantic. The distances travelled ranged from 2,270 to 2,770 kilometers,” DeLuca says.

To prepare for the flight, the birds build up their fat stores, explains Canadian team leader Ryan Norris of the University of Guelph. “They eat as much as possible, in some cases doubling their body mass in fat so they can fly without needing food or water. For blackpolls, they don’t have the option of failing or coming up a bit short. It’s a fly-or-die journey that requires so much energy.”

He adds, “These birds come back every spring very close to the same place they used in the previous breeding season, so with any luck you can catch them again. Of course there is high mortality among migrating songbirds on such a long journey, we believe only about half return.”

Chris Rimmer, an ornithologist at the Vermont Center for Ecostudies notes, “We’ve only sampled this tiny part of their breeding range. We don’t know what birds from Alaska do, for example. This may be one of the most abundant warblers in North America, but little is known about its distribution or ecology on the wintering grounds in Venezuela and the Amazon. However, there is no longer any doubt that the blackpoll undertakes one of the most audacious migrations of any bird on earth.”

DeLuca says, “It was pretty thrilling to get the return birds back, because their migratory feat in itself is on the brink of impossibility. We worried that stacking one more tiny card against their success might result in them being unable to complete the migration. Many migratory songbirds, blackpolls included, are experiencing alarming population declines for a variety of reasons, if we can learn more about where these birds spend their time, particularly during the nonbreeding season, we can begin to examine and address what might be causing the declines.”

As for why the blackpoll undertakes such a perilous journey while other species follow a longer but safer coastal route, the authors say that because migration is the most perilous part of a songbird’s year, it may make sense to get it over with as quickly as possible. However, this and other questions remain to be studied.

Other researchers on the team besides those from UMass Amherst, the University of Guelph and the Vermont Center for Ecostudies, were from the Smithsonian Conservation Biology Institute, Acadia University, Bird Studies Canada and the University of Exeter, U.K. Each contributed to funding the study.

Light-level geolocators reveal that Veeries instinctively follow the shortest possible #migration path: here.

Rotate a warbler in 3D, distinguish similar-sounding songs with spectrograms, or identify a warbler using clues from plumage and song at the same time. With this new app from The Warbler Guide authors Tom Stephenson and Scott Whittle, ID tips leap off the page onto your mobile device in a whole new way. Read our review.

Male, female wrens singing duets


This video says about itself:

Plain-Tailed Wrens‘ Songs

7 November 2011

Long-married human couples may finish each others’ sentences, but the plain-tailed wrens of the Andes take things a step further. Male and female wrens sing intimate duets in which they alternate syllables so quickly it sounds like a single bird is singing. New research shows that the brains of both the male and female wrens actually process the entire duet, not just each bird’s own contribution.

Dr. Fortune plays some examples of plain-tailed wrens’ songs.

This video about plain-tailed wrens says about itself:

3 November 2011

Wrens’ Brains Are Wired for Duets

And this video is the sequel.

Plain-tailed wrens are not the only wrens singing duets. So do other wren species, especially in tropical countries; eg, band-backed wrens.

The plant family Corsiaceae, new research


This video is called Liliaceae plant family, description, examples, info.

From the Journal of Biogeography:

Ancient Gondwana break-up explains the distribution of the mycoheterotrophic family Corsiaceae (Liliales)

19 FEB 2015

Abstract

Aim

Many plant families have a disjunct distribution across the southern Pacific Ocean, including the mycoheterotrophic family Corsiaceae, which provides a prime example of this biogeographical pattern. A better grasp of the family’s evolutionary relationships is needed to understand its historical biogeography. We therefore aimed to (1) test the uncertain monophyly of Corsiaceae, (2) define its phylogenetic position, and (3) estimate divergence times for the family, allowing us to assess whether the distribution of the family is the result of vicariance.

Location

Southern South America and Australasia.

Methods

We analysed various combinations of mitochondrial and nuclear data to address the monophyly, phylogenetic position and age of Corsiaceae. To test its monophyly, we used a three-locus data set including most monocot orders, and to infer its exact phylogenetic position, we used a five-locus extended data set. We corroborated these findings using an independent plastome dataset. We then used a two-locus dataset with taxa from all monocot orders, and a three-locus dataset containing only taxa of Liliales, to estimate divergence times using a fossil-calibrated uncorrelated lognormal relaxed-clock approach.

Results

Corsiaceae is a monophyletic family and the sister group of Campynemataceae. This clade is the sister group of all other Liliales. The crown age of Corsiaceae is estimated to be 53 Ma (95% confidence interval 30–76 Ma).

Main conclusions

Corsiaceae is an ancient family of mycoheterotrophic plants, whose crown age overlaps with the plate-tectonic split of Gondwana, consistent with a vicariance-based explanation for its current distribution.

See also here.

South American hummingbird has improved Internet page


This is a video about a little hermit, a hummingbird species from the north of South America.

New on Neotropical Birds Online: completed account for Little Hermit (Phaethornis longuemareus) by Linh Huynh: here.