Biologists Race to Save Nearly Extinct Florida Bird

19 April 2013 - Even though the project didn't snag a hoped-for grant, federal officials said Thursday they have decided to proceed with plans to collect eggs from the nests of one of the most endangered species in North America — the Florida grasshopper sparrow — in hopes of preventing its extinction.

Researchers fear the small, elusive bird, now clinging to survival in three Central Florida parklands, could vanish within a few years.

U.S. Fish and Wildlife Service officials said the captive-breeding program will consist of volunteers and staff from their agency, the state Fish and Wildlife Conservation Commission and the state Park Service. Teams will attempt to collect eggs through early summer, taking them to the Rare Species Conservatory Foundation in Loxahatchee.

Hatchlings will be kept in captivity in a years-long effort to establish a population of birds that eventually could help bolster the health of sparrows still existing in the wild — or serve as pioneers in re-establishing a wild population should the current one go extinct.

Several university and private researchers have criticized the federal agency, harshly in some cases, for giving the sparrows a low priority as their numbers dipped alarmingly and inexplicably in recent years. The birds rely on vast, treeless prairies, but much of that habitat has been paved by development or plowed under by agriculture.

Researchers are vexed by the birds' decline in part because the public lands where they still exist, including Three Lakes Wildlife Management Area and Kissimmee Prairie Preserve State Park, have been intensively managed to suit the sparrows' needs. Invading fire ants are suspected to play a role in the decline.

The Fish and Wildlife Service said it will cobble together dollars from various sources to support further research and the captive-breeding work.

Ocean Acidification as a Hearing Aid for Fish?

Apr. 19, 2013 — Ocean acidification, which occurs as CO₂ is absorbed by the world's oceans, is a source of concern for marine scientists worldwide. Studies on coral, mollusks, and other ocean denizens are helping to paint a picture of what the future might entail for specific species, should carbon emissions continue to increase.

In a new study published in Global Change Biology, University of Miami (UM) Rosenstiel School of Marine & Atmospheric Science researchers Sean Bignami, Su Sponaugle, and Robert Cowen are the first to study the effects of acidification on the larvae of cobia (Rachycentron canandum). Cobia are large tropical fish that spawn in pelagic waters, highly mobile as they mature, and a popular species among recreational anglers.

The team reared cobia in tanks with different levels of CO₂ saturation looking for effects on growth, development, otolith (ear stone) formation, swimming ability, and activity level during the vulnerable larval stage of these fish. 

They found that cobia showed remarkable resistance to end-of-century acidification scenarios in terms of growth, development, and activity. However, more extreme acidification scenarios caused reduced larval size and a 2-3 day delay in their development. The study also reports a significant increase in otolith size at the most mild acidification conditions reported to date.

"The larval period is a critical stage in the marine fish lifecycle and the ability of cobia larvae to withstand 'business-as-usual' scenarios of ocean acidification provides an optimistic outlook for this species. However, research on this topic is still limited and if our findings on otolith formation are any indicator, then these fish are not entirely resistant to acidification," said Bignami, a Marine Biology and Fisheries PhD candidate at UM.

The study is the first to report impacts of ocean acidification on a large, pelagic tropical fish species. 

"We need additional studies on study how fish, especially those that are ecologically and economically important, react to these environmental changes if we want to find ways to potentially mitigate the effects," Bignami added.

Cobia larvae used in this study were produced from broodstock raised at the UM Experimental Hatchery.

Scientists Reverse Memory Loss in Animal Brain Cells

Apr. 17, 2013 — Neuroscientists at The University of Texas Health Science Center at Houston (UTHealth) have taken a major step in their efforts to help people with memory loss tied to brain disorders such as Alzheimer's disease.

Using sea snail nerve cells, the scientists reversed memory loss by determining when the cells were primed for learning. The scientists were able to help the cells compensate for memory loss by retraining them through the use of optimized training schedules. Findings of this proof-of-principle study appear in the April 17 issue ofThe Journal of Neuroscience.

"Although much works remains to be done, we have demonstrated the feasibility of our new strategy to help overcome memory deficits," said John "Jack" Byrne, Ph.D., the study's senior author, as well as director of the W.M. Keck Center for the Neurobiology of Learning and Memory and chairman of the Department of Neurobiology and Anatomy at the UTHealth Medical School.

This latest study builds on Byrne's 2012 investigation that pioneered this memory enhancement strategy. The 2012 study showed a significant increase in long-term memory in healthy sea snails called Aplysia californica, an animal that has a simple nervous system, but with cells having properties similar to other more advanced species including humans.

Yili Zhang, Ph.D., the study's co-lead author and a research scientist at the UTHealth Medical School, has developed a sophisticated mathematical model that can predict when the biochemical processes in the snail's brain are primed for learning.

Her model is based on five training sessions scheduled at different time intervals ranging from 5 to 50 minutes. It can generate 10,000 different schedules and identify the schedule most attuned to optimum learning.

"The logical follow-up question was whether you could use the same strategy to overcome a deficit in memory," Byrne said. "Memory is due to a change in the strength of the connections among neurons. In many diseases associated with memory deficits, the change is blocked."

To test whether their strategy would help with memory loss, Rong-Yu Liu, Ph.D., co-lead author and senior research scientist at the UTHealth Medical School, simulated a brain disorder in a cell culture by taking sensory cells from the sea snails and blocking the activity of a gene that produces a memory protein. This resulted in a significant impairment in the strength of the neurons' connections, which is responsible for long-term memory.

To mimic training sessions, cells were administered a chemical at intervals prescribed by the mathematical model. After five training sessions, which like the earlier study were at irregular intervals, the strength of the connections returned to near normal in the impaired cells.

"This methodology may apply to humans if we can identify the same biochemical processes in humans. Our results suggest a new strategy for treatments of cognitive impairment. Mathematical models might help design therapies that optimize the combination of training protocols with traditional drug treatments," Byrne said.

He added, "Combining these two could enhance the effectiveness of the latter while compensating at least in part for any limitations or undesirable side effects of drugs. These two approaches are likely to be more effective together than separately and may have broad generalities in treating individuals with learning and memory deficits."

Other co-authors from the UTHealth Medical School included: Douglas A. Baxter, Ph.D., professor; Paul Smolen, Ph.D., assistant professor; and Len Cleary, Ph.D., professor.

Love at First Sniff: Male Moths Go by First Impressions

Apr. 16, 2013 — An international team of researchers, including an entomologist at the University of California, Riverside, has an explanation for why we see so many hybrid moths in nature. The team closely examined the behavior and the olfactory circuitry of male moths and found an answer in female-produced pheromones -- chemicals generally consisting of a blend of two to several derivatives of fatty acids.

Male moths use pheromones to find females. To avoid mating with the wrong moth species, the pheromone blends are specific for each moth species, with only males of the same species "understanding" these volatile messages -- a result shown many times during the last 40 years of research on moth pheromones. The researchers focused on the European corn borer, a moth species in which males often mate with females from a different strain.

Strains are variants, forms of the same species. While two different species cannot mate with each other, strains, being from the same species, can.

To understand the mating behavior of the European corn borer, first, the researchers followed the flights of males to female pheromones in a wind tunnel. Each strain of the European corn borer uses a blend of pheromone components in a very specific ratio. But to their surprise, the researchers found that as the male moth flies upwind along the pheromone plume, its olfactory circuitry loses the ability to measure this ratio.

"This happens because receptors in the moth brain for each pheromone component have differential rates of sensory adaptation and each type of receptor begins to fire at a different rate, causing the input into the moth's brain to change as the moth flies along the plume," explained Teun Dekker, a former UCR graduate student and now an associate professor at the Swedish University of Agricultural Sciences, and a coauthor on the study. "To overcome this mismatch, moths rely on the ratio they detected in their first encounter with the plume."

According to the researchers, this "mental short cut" is needed for male moths to continue their orientation along the plumes which, from a sensory input viewpoint, seem to be changing in pheromone component ratio.

"Once male moths lock onto a pheromone plume, they are much less attuned to blend quality," Dekker said. "In other words, males fly even to blends that were initially unattractive, and so can mate with females of different strains that they would not have approached otherwise, explaining why we find hybrid moths in nature."

Study results appeared online April 15 in the Proceedings of the National Academy of Sciences.

Experimental details

The researchers conducted a series of behavioral experiments with overlapping pheromone plumes as well as plumes that sharply transitioned from one blend to another in a wind tunnel at the Swedish University of Agricultural Sciences. They chose the European corn borer moth to study for its narrow tuning to a binary blend of female-produced 14-carbon-chainlength acetates, called here Z11 and E11 for simplicity. Two strains exist, the Z and E strains, which produce and prefer blends of differing ratios of the Z11 to E11 pheromone components.

The researchers installed pheromone lures of each strain in the wind tunnel, as well as an intermediate, hybrid lure. Next they exposed males to the partially overlapping pheromone plumes released by these lures, thus mimicking plumes occurring in nature when a large number of moths are present.

They found that males were initially attracted to lures releasing pheromones produced by females of their own strain. But after taking flight, the males "relax their specificity," that is, they are less particular about which lures they fly to. For example, in a choice between three partially overlapping pheromone sources in one experiment, 58 percent, 38 percent and 4 percent of Z-strain males landed on Z, H and E lures, respectively.

"What we generally recognize as a distinctive smell -- the scent of a flower or the aroma of coffee -- typically consists of a mixture of many different chemicals," said study coauthor Ring Cardé, a distinguished professor of entomology who holds the Alfred M. Boyce Chair in the UCR Department of Entomology. "This is the signature of a particular bouquet -- the presence of a blend of many chemicals often in specific ratios. Our work suggests that it could be the first impression -- the first whiff of odor -- that determines the ability of an insect to recognize that odor mixture."

Next, the researchers will examine if a response specific to odor blends is altered in other moth species and organisms such as mosquitoes after their first encounter with an odor mixture.

Zsolt Kárpáti at the Hungarian Academy of Sciences and Marco Tasin at the Swedish University of Agricultural Sciences also contributed to the study. Dekker worked in Cardé's lab, graduating from UCR with a doctoral degree in 2002.

Cardé, who spent three months in 2011 in Sweden to conduct the research, was supported by a grant from the Swedish Royal Academy of Natural Sciences, Medicine and Technology.

Alternative Way to Explain Life's Complexity Proposed

Apr. 12, 2013 — Evolution skeptics argue that some biological structures, like the brain or the eye, are simply too complex for natural selection to explain. Biologists have proposed various ways that so-called 'irreducibly complex' structures could emerge incrementally over time, bit by bit. But a new study proposes an alternative route.

Instead of starting from simpler precursors and becoming more intricate, say authors Dan McShea and Wim Hordijk, some structures could have evolved from complex beginnings that gradually grew simpler -- an idea they dub "complexity by subtraction."       Computer models and trends in skull evolution back them up, the researchers show in a study published this week in the journalEvolutionary Biology.

Some biological structures are too dizzyingly complex to have emerged stepwise by adding one part and then the next over time, intelligent design advocates say. Consider the human eye, or the cascade that causes blood to clot, or the flagellum, the tiny appendage that enables some bacteria to get around. Such all-or-none structures, the argument goes, need all their parts in order to function. Alter or take away any one piece, and the whole system stops working. In other words, what good is two thirds of an eye, or half of a flagellum?

For the majority of scientists, the standard response is to point to simpler versions of supposedly 'irreducibly complex' structures that exist in nature today, such as cup eyes in flatworms. Others show how such structures could have evolved incrementally over millions of years from simpler precursors. A simple eye-like structure -- say, a patch of light-sensitive cells on the surface of the skin -- could evolve into a camera-like eye like what we humans and many other animals have today, biologists say.

"Even a very simple eye with a small number of parts would work a little. It would be able to detect shadows, or where light is coming from," said co-author Dan McShea of Duke University.

In a new study, McShea and co-author Wim Hordijk propose an alternative route. Instead of emerging by gradually and incrementally adding new genes, cells, tissues or organs over time, what if some so-called 'irreducibly complex' structures came to be by gradually losing parts, becoming simpler and more streamlined? Think of naturally occurring rock arches, which start as cliffs or piles of stone and form when bits of stone are weathered away. They call the principle 'complexity by subtraction.'

"Instead of building up bit by bit from simple to complex, you start complex and then winnow out the unnecessary parts, refining them and making them more efficient as you go," McShea said.

A computer model used by co-author Wim Hordijk supports the idea. In the model, complex structures are represented by an array of cells, some white and some black, like the squares of a checkerboard. In this class of models known as cellular automata, the cells can change between black and white according to a set of rules.

Using a computer program that mimics the process of inheritance, mutation, recombination, and reproduction, the cells were then asked to perform a certain task. The better they were at accomplishing the task, the more likely they were to get passed on to the next generation, and over time a new generation of rules replaced the old ones. In the beginning, the patterns of black and white cells that emerged were quite complex. But after several more generations, some rules 'evolved' to generate simpler black and white cell patterns, and became more efficient at performing the task, Hordijk said.

We see similar trends in nature too, the authors say. Summarizing the results of previous paleontological studies, they show that vertebrate skulls started out complex, but have grown simpler and more streamlined. 

"For example, the skulls of fossil fish consist of a large number of differently-shaped bones that cover the skull like a jigsaw puzzle," McShea said. "We see a reduction in the number of skull bone types in the evolutionary transitions from fish to amphibian to reptile to mammal." 

In some cases skull bones were lost; in other cases adjacent bones were fused. Human skulls, for example, have fewer bones than fish skulls.

Computer simulations like Hordijk's will allow scientists to test ideas about how often 'complexity by subtraction' happens, or how long it takes. The next step is to find out how often the phenomenon happens in nature.

"What we need to do next is pick an arbitrary sample of complex structures and trace their evolution and see if you can tell which route they proceeded by, [from simple to complex or the opposite]. That will tell us whether this is common or not," McShea added.

Self-Medication in Animals Much More Widespread Than Believed

Apr. 11, 2013 — It's been known for decades that animals such as chimpanzees seek out medicinal herbs to treat their diseases. But in recent years, the list of animal pharmacists has grown much longer, and it now appears that the practice of animal self-medication is a lot more widespread than previously thought, according to a University of Michigan ecologist and his colleagues.

Animals use medications to treat various ailments through both learned and innate behaviors. The fact that moths, ants and fruit flies are now known to self-medicate has profound implications for the ecology and evolution of animal hosts and their parasites, according to Mark Hunter, a professor in the Department of Ecology and Evolutionary Biology and at the School of Natural Resources and Environment.

In addition, because plants remain the most promising source of future pharmaceuticals, studies of animal medication may lead the way in discovering new drugs to relieve human suffering, Hunter and two colleagues wrote in a review article titled "Self-Medication in Animals," to be published online today in the journal Science.

"When we watch animals foraging for food in nature, we now have to ask, are they visiting the grocery store or are they visiting the pharmacy?" Hunter said. "We can learn a lot about how to treat parasites and disease by watching other animals."

Much of the work in this field has focused on cases in which animals, such as baboons and woolly bear caterpillars, medicate themselves. One recent study has suggested that house sparrows and finches add high-nicotine cigarette butts to their nests to reduce mite infestations.

But less attention has been given to the many cases in which animals medicate their offspring or other kin, according to Hunter and his colleagues. Wood ants incorporate an antimicrobial resin from conifer trees into their nests, preventing microbial growth in the colony. Parasite-infected monarch butterflies protect their offspring against high levels of parasite growth by laying their eggs on anti-parasitic milkweed.

Hunter and his colleagues suggest that researchers in the field should "de-emphasize the 'self' in self-medication" and base their studies on a more inclusive framework.

"Perhaps the biggest surprise for us was that animals like fruit flies and butterflies can choose food for their offspring that minimizes the impacts of disease in the next generation," Hunter said. "There are strong parallels with the emerging field of epigenetics in humans, where we now understand that dietary choices made by parents influence the long-term health of their children."

The authors argue that animal medication has several major consequences on the ecology and evolution of host-parasite interactions. For one, when animal medication reduces the health of parasites, there should be observable effects on parasite transmission or virulence.

For example, when gypsy moth caterpillars consume foliage high in certain toxic compounds, transmission of viruses between the caterpillars is reduced, facilitating moth outbreaks.

In addition, animal medication should affect the evolution of animal immune systems, according to Hunter and his colleagues. Honeybees are known to incorporate antimicrobial resins into their nests. Analysis of the honeybee genome suggests that they lack many of the immune-system genes of other insects, raising the possibility that honeybees' use of medicine has been partly responsible -- or has compensated -- for a loss of other immune mechanisms.

The authors also note that the study of animal medication will have direct relevance for human food production. Disease problems in agricultural organisms can worsen when humans interfere with the ability of animals to medicate, they point out.

For example, increases in parasitism and disease in honeybees can be linked to selection by beekeepers for reduced resin deposition by their bees. A reintroduction of such behavior in managed bee colonies would likely have great benefits for disease management, the authors say.

The first author of the Science paper is Jacobus de Roode of Emory University. The other author is Thierry Lefevre of the Institut de Recherche pour le Developpement in France.

Goosefish Capture Small Puffins Over Deep Water of Northwest Atlantic

Apr. 10, 2013 — A recent study has shown that bottom-dwelling goosefish, also known as monkfish, prey on dovekies, a small Arctic seabird and the smallest member of the puffin family. To understand how this deep-water fish finds a shallow-feeding bird in offshore waters, researchers looked at when, where, and how these animals were most likely to be in the same place at the same time.

Remains of fourteen dovekie were recovered from the stomachs of 14 goosefish caught during the winters between 2007 and 2010. The goosefish were captured in gillnets deployed at depths between 275 and 495 feet in waters 65 to 95 miles south of Chatham, Mass. The Cape Cod Commercial Hook Fishermen's Association collected the specimens and provided them for the research study.

Researchers from NOAA's Northeast Fisheries Science Center (NEFSC) in Woods Hole, Mass. and the USGS Patuxent Wildlife Research Center in Laurel, Md., wanted to know how the birds could be captured so far from shore by a fish that lives on the ocean bottom in deep water. Their findings, recently published online in the Northeastern Naturalist, suggest that it is all a matter of timing.

Goosefish (Lophius americanus) are highly opportunistic predators. Distributed from the Gulf of Maine to Cape Hatteras, N.C., the fish are typically partially buried on soft bottom habitats and attract a variety of prey by using a modified dorsal fin ray that resembles a fishing pole and lure.

Dovekies, a small black and white puffin species, breed along the Arctic coast and head south in the winter, typically as far as New England. The dovekie (Alle alle), also known as little auk, is the smallest of the auks. It lives in the open ocean and can dive to depths of more than 100 feet to prey on small fish, crustaceans, and zooplankton.

Study co-author Anne Richards of the NEFSC says tagging studies that she and colleagues have conducted reveal that goosefish swim considerable vertical distances from the bottom to near the surface, especially during their spring and fall migrations onshore and offshore in response to water temperatures and related factors.

Goosefish leave the bottom to use the currents during migration periods or to spawn at the surface. If prey items are encountered during their vertical movements, the goosefish take advantage. Hence, timing may be the key factor in bringing dovekies and goosefish together in the same place.

"Given the common name 'goosefish', it is not surprising to find birds in goosefish stomachs, but it is surprising to find that this predation occurs over deep water, "Richards said. "Goosefish do not actively seek out the dovekies, but when such tasty morsels are available in the water column, the fish are going to consume them."

Another source of data used in the study is the NOAA NEFSC food-habits database, which contains decades of predation information collected from the stomachs of fish that are caught during regular research vessel surveys. While not a particularly good measure of how often or how many birds are eaten by fish, these data confirm that not only goosefish, but also spiny dogfish, Atlantic herring, pollock, Atlantic cod, red hake, and fourspot flounder will eat birds.

Lead author Matthew Perry, a research wildlife biologist at the USGS Patuxtent Wildlife Research Center, says he became interested in goosefish predation when he learned from a sea scalloper on Nantucket that Chatham gillnetters were finding birds inside goosefish stomachs.

"I was studying long-tailed ducks and thought, to avoid being eaten, these birds fly 30 to 50 miles to Nantucket Sound each night and return to the ocean in the morning," said Perry, who studies several species of seaducks. "People ask why don't dovekies fly to Nantucket Sound at night like the long-tailed ducks to avoid goosefish? My explanation is that dovekies have small wings and can't make the routine flight."

"One thing we know is that dovekies cannot dive to the bottom in 300 to 400 feet of water," Perry said. "Goosefish probably come up from the ocean bottom to within 10 to 20 feet of the water surface at night. As dovekies dive for amphipods, small crustaceans, in the morning at first light, goosefish seize the opportunity and might use their 'fishing lure' to simulate one of these prey species by attracting the dovekies with their typical 'sit and wait' behavior."

The magnitude of fish predation on seabirds is poorly understood. Perry says most food habit studies for goosefish have been conducted during summer when the dovekies have migrated north to their Arctic breeding areas; thus, they seldom have been recorded as prey. Perry hopes more telemetry tracking of goosefish will be done in winter when birds are in the area and are potential prey.

As for what's ahead, Richards says ongoing use of electronic tags on goosefish will provide more information on their vertical movements.

New Genus of Bat Discovered in South Sudan

Niumbaha superba

Apr. 9, 2013 Researchers have identified a new genus of bat after discovering a rare specimen in South Sudan.

 With wildlife personnel under the South Sudanese Ministry of Wildlife Conservation and Tourism, Bucknell Associate Professor of Biology DeeAnn Reeder and Fauna & Flora International (FFI) Programme Officer Adrian Garside were leading a team conducting field research and pursuing conservation efforts when Reeder spotted the animal in Bangangai Game Reserve.

"My attention was immediately drawn to the bat's strikingly beautiful and distinct pattern of spots and stripes. It was clearly a very extraordinary animal, one that I had never seen before," recalled Reeder. "I knew the second I saw it that it was the find of a lifetime."

After returning to the United States, Reeder determined the bat was the same as one originally captured in nearby Democratic Republic of the Congo in 1939 and namedGlauconycteris superba, but she and colleagues did not believe that it fit with other bats in the genusGlauconycteris.

"After careful analysis, it is clear that it doesn't belong in the genus that it's in right now," Reeder said. "Its cranial characters, its wing characters, its size, the ears -- literally everything you look at doesn't fit. It's so unique that we need to create a new genus."

In the paper, "A new genus for a rare African vespertilionid bat: insights from South Sudan" just published by the journalZooKeys, Reeder, along with co-authors from the Smithsonian Institution and the Islamic University in Uganda, placed this bat into a new genus -- Niumbaha. The word means "rare" or "unusual" in Zande, the language of the Azande people in Western Equatoria State, where the bat was captured. The bat is just the fifth specimen of its kind ever collected, and the first in South Sudan, which gained its independence in 2011.

"To me, this discovery is significant because it highlights the biological importance of South Sudan and hints that this new nation has many natural wonders yet to be discovered. South Sudan is a country with much to offer and much to protect," said Matt Rice, FFI's South Sudan country director. FFI is using its extensive experience of working in conflict and post-conflict countries to assist the South Sudanese government as it re-establishes the country's wildlife conservation sector and is also helping to rehabilitate selected protected areas through training and development of park staff and wildlife service personnel, road and infrastructure development, equipment provision, and supporting research work. || Read more about FFI's conservation efforts in South Sudan here.

The team's research in South Sudan was made possible by a $100,000 grant that Reeder received from the Woodtiger Fund. The private research foundation recently awarded Reeder another $100,000 dollar grant to continue her research this May and to support FFI's conservation programs.

"Our discovery of this new genus of bat is an indicator of how diverse the area is and how much work remains," Reeder added. "Understanding and conserving biodiversity is critical in many ways. Knowing what species are present in an area allows for better management. When species are lost, ecosystem-level changes ensue. I'm convinced this area is one in which we need to continue to work."

Original Article

A Poem: "The Oak Tree" by Johnny Ray Ryder Jr.

The Oak Tree

by Johnny Ray Ryder Jr.

A mighty wind blew night and day.

It stole the Oak Tree's leaves away.

Then snapped its boughs

and pulled its bark

until the Oak was tired and stark.

But still the Oak Tree held its ground

while other trees fell all around.

The weary wind gave up and spoke,

"How can you still be standing Oak?"

The Oak Tree said, I know that you

can break each branch of mine in two,

carry every leaf away,

shake my limbs and make me sway.

But I have roots stretched in the earth,

growing stronger since my birth.

You'll never touch them, for you see

they are the deepest part of me.

Until today, I wasn't sure

of just how much I could endure.

But now I've found with thanks to you,

I'm stronger than I ever knew.