Time ticks away at wild bison genetic diversity

NOVEMBER 3, 2019

by Morgan Lee

Evidence is mounting that wild North American bison are gradually shedding their genetic diversity across many of the isolated herds overseen by the U.S. government, weakening future resilience against disease and climate events in the shadow of human encroachment.

The extent of the creeping threat to herds overseen by the Department of Interior—the backbone of wild bison conservation efforts for North America—is coming into sharper focus amid advances in genetic studies.

Preliminary results of a genetic population analysis commissioned by the National Park Service show three small federal herds would almost certainly die off—extinguishing their DNA lineage—within 200 years under current management practices that limit transfers for interbreeding among distant herds.

The study is awaiting peer review by other scientists. It does not include Yellowstone National Park's herd of some 5,000 unfenced bison, the largest federal conservation herd that's seen by millions of people who visit the park annually.

"Some of these herds that lost the most genetic diversity do have a high probability of going extinct, due to the accumulation of inbreeding," explained Cynthia Hartway, a conservation scientist at the bison program with Wildlife Conservation Society who led the analysis.

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The recent spread of coyotes across North America did not doom deer populations

Date:  March 20, 2019

Source:  North Carolina Museum of Natural Sciences

Coyotes eat deer, but not enough to limit the deer population at a large scale. A new study of deer numbers across the eastern United States has found that the arrival and establishment of coyote predators has not caused the number of deer harvested by hunters to decline.

"With wolves and cougars extinct in most of the eastern U.S., white-tailed deer have become abundant, sometimes overabundant," says Roland Kays, wildlife biologist at the North Carolina Museum of Natural Sciences and North Carolina State University, and co-author of a paper describing this research. "Coyotes moved in as the new top predator of the east, but they aren't nearly as effective deer hunters as wolves, so there's been a lot of controversy about whether these medium-sized predators can really limit deer populations at large scales."

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Oldest frog relative found in North America

Date:  February 27, 2019

Source:  Virginia Tech

A team of paleontologists led by Virginia Tech's Michelle Stocker and Sterling Nesbitt of the Department of Geosciences have identified fossil fragments of what are thought to be the oldest known frogs in North America.

The fossils are comprised of several small pieces of hip bone, called an ilium, from Chinle frogs, a distant long-extinct branch of, but not a direct ancestor of, modern frogs. The fragments are packed into rock and are smaller than a pinky nail. They represent the first known and earliest equatorial remains of a salientian -- the group containing living frogs, and their most-closely related fossil relatives -- from the Late Triassic, roughly 216 million years ago.

The name of the fossil derives from where they were found, the Chinle Formation of Arizona.

Stocker, an assistant professor of geosciences in the Virginia Tech College of Science, says the fossils, discovered in May 2018, underscore the importance of microfossil collection and analysis for understanding extinct species whose total length is under three feet in length.

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A new hope: One of North America's rarest bees has its known range greatly expanded

Date:  April 16, 2018

Source:  Pensoft Publishers

The Macropis Cuckoo Bee is one of the rarest bees in North America, partly because of its specialized ecological associations. It is a nest parasite of oil-collecting bees of the genus Macropis which, in turn, are dependent on oil-producing flowers of the genus Lysimachia.

In fact, the cuckoo bee -- which much like its feather-bearing counterpart does not build a nest of its own, but lays its eggs in those of other species instead -- is so rare that it was thought to have gone extinct until it was collected in Nova Scotia, Canada, in the early 2000s. As a result, the Macropis Cuckoo Bee was brought to the attention of the Committee on the Status of Endangered Wildlife in Canada (COSEWIC).

Recently, an individual reported from Alberta, Canada, brought new hope for the survival of the species. In addition to previously collected specimens from Ontario, this record greatly expands the known range of the cuckoo.

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A race against pine: Wood-boring wasp in North America threatened by a Eurasian invader

Date:  January 22, 2018

Source:  Pensoft Publishers

Summary:

Invasive species have diverse impacts in different locations, including biodiversity loss, as a result of native species being outcompeted for similar resources. A US research team studied the case of an aggressive Eurasian woodwasp that has recently established in North America and poses a threat to a native competitor species.

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A horse is a horse, of course, of course -- except when it isn't

Analysis of ancient DNA reveals a previously unrecognized genus of extinct horses that once roamed North America

Date:  November 28, 2017

Source:  University of California - Santa Cruz

Summary:

Scientists have discovered a previously unrecognized genus of extinct horses that roamed North America during the last ice age. The new findings are based on an analysis of ancient DNA from fossils of the enigmatic 'New World stilt-legged horse' excavated from sites such as Natural Trap Cave in Wyoming, Gypsum Cave in Nevada, and the Klondike goldfields of Canada's Yukon Territory.

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An alternative to wolf control to save endangered caribou

Researchers study the effectiveness of a new government strategy to stabilize the caribou population by focusing on the reduction of invasive moose populations, indirectly lowering the density of the caribou's primary predator

Date: August 29, 2017

Source: PeerJ

Summary:

The iconic woodland caribou across North America face increasing predation pressures from wolves. A short-term solution to caribou conservation would be to kill wolves. But a new government policy looks at reducing the invasive species moose numbers propping up the wolf population. Researchers have now evaluated the effects of this policy on the caribou population.

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Tiny Asian beetle wreaking havoc on North America's ash trees

August 9, 2016 by Nova Safo

The Emerald Ash Borer targets the ash tree, a common variety in Midwestern US cities, where the tree can survive cramped sidewalks, harsh winters and road salts

Over the next two years, grounds crews in St. Louis will cut down nearly one out of every five trees, altering the US city's leafy landscape for at least a generation.

The Midwestern metropolis made the tough decision with the knowledge that if it does not cut down the trees, most will quickly die.

St. Louis is the latest victim of the Emerald Ash Borer, an Asian beetle smaller than a penny, which emigrated from China via shipping materials and is destroying millions of trees in North America.

The insect targets the Ash tree—a common variety in Midwestern cities, where the tree can survive cramped sidewalks, harsh winters and road salts used to keep streets clear of ice and snow.

In St. Louis, city forestry commissioner Skip Kincaid is tasked with dealing with the invasive pest and the destruction it is expected to cause in the next few years.

"I'm trying as best I can to enlighten the public about how devastating it is going to be," Kincaid said.

To head off the Emerald Ash Borer's advance, Kincaid will cut down almost all of the city's 14,000 Ash trees—or roughly 17 percent of all trees—over the next two years.

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North America Has Only 1 True Species of Wolf, DNA Shows

By Megan Gannon, Live Science Contributor | July 29, 2016 07:04am ET

DNA tests of wolves across North America suggest that there is just one species of the canid: the gray wolf.

What's more, populations of red wolves and eastern wolves, thought to be distinct species, are actually just hybrids of gray wolves and coyotes that likely emerged in the last couple hundred years, the study found.

The findings, published in the journal Science Advances on Wednesday (July 27), could have implications for the conservation of wolves considered endangered in the United States, the researchers say.

Shared genes
For the study, scientists sequenced the whole genomes of 28 canids, including gray wolves, eastern wolves, red wolves and coyotes in North America.

The study revealed that gray wolves and coyotes are not very different from each other, genetically speaking. According to the DNA results, the two species likely diverged from a common ancestor in Eurasia about 50,000 years ago —much more recently than previous estimates of 1 million years ago.

Meanwhile, red wolves, thought to be native to the southeastern United States, and eastern wolves from the Great Lakes region, were found to be genetic hybrids.

"These gray-wolf-coyote hybrids look distinct and were mistaken as a distinct species," study author Robert Wayne, a professor of ecology and evolutionary biology at the University of California, Los Angeles, said in a statement.

Compared with eastern wolves, red wolves were more coyote-like in their genetic makeup, the study found, which makes sense historically. Before the hybridization, humans dramatically altered the habitat of wolves in the southeastern U.S. Once gray wolves started to get hunted out of the region, the hybrid red wolves could mate only with other hybrids and coyotes, the researchers said.

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Saving north america's salamanders, newts

Date: May 30, 2016

Source: University of Saskatchewan

The fate of the world's richest biodiversity of salamanders and newts is in the hands of pet owners across North America, said Natacha Hogan, an environmental toxicologist specializing in amphibians at the University of Saskatchewan.

At issue is salamander chytrid disease, caused by a fungus that infects both salamanders and newts with near total lethality. The fungus, known as B.sal, infects the skin, causing wart-like lesions. As the disease progresses, the animal stops eating, becomes lethargic, loses control of its body movements and eventually dies.

Originally from Asia, the disease has completely wiped out wild populations where it has appeared in Europe and the UK, said Hogan.

"It's basically the pet trade," she said. "It's when you start moving salamanders; this is what this spread has been attributed to. There have been millions of salamanders imported -- how many kids own fire belly newts from a pet store?"

While the fungus has not yet been spotted in Canada, she said the U.S. has already instituted strict regulations on trade in salamanders and newts.

The Canadian Wildlife Health Cooperative (CWHC) is leading efforts to raise the alarm, urging immediate action. The group compares the threat to a similar invasive fungal disease that all but wiped out entire species of frogs in South and Central America, and white nose disease, which has killed entire colonies of bats -- millions of animals -- across North America, including Canada.

While Canada has only two species of newt -- both in Ontario -- salamanders are wide spread, Hogan said, with about 15 species across the country. Some of these have a small geographic range, but others, such as the two species of tiger salamander found in Saskatchewan, can be found right across the Prairie Provinces.

The rest of North America is even more richly endowed.

"The U.S. has among the greatest biodiversity of amphibians in the world, so this is also true of salamanders and newts," Hogan said.

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New study investigates the environmental cues dolphins use to migrate on the Atlantic coast of North America

Date: April 22, 2016

Source: De Gruyter

Seasonal migration patterns of bottlenose dolphins -- what we know for sure? With the changing of the seasons comes the urge to migrate for many animals of the world, whether they be furred, feathered, or even finned. One finned animal in particular, the common bottlenose dolphin, undertakes seasonal migrations each spring and fall, but how the dolphins know when to migrate has not always been clear. It was usually assumed that their southern migration begins when the ocean waters drop in temperature. However, until now there was little evidence to support this and it was largely unknown what factors influence the initiation of dolphin migration. A new study has discovered some of the factors that influence these seasonal migrations.

In the article, published this week and available online, Masters student Anna Taylor, from the University of Georgia (USA), and colleagues studied the common bottlenose dolphin, which migrates seasonally along the southeastern United States Atlantic coast. While this species of dolphin is widely studied, surprisingly little is known about what influences the timing of these migrations.

The scientists needed to track the comings and goings of dolphins at their study sites on the Georgia and South Carolina coasts, and they did so using photographic identification of individual dolphin fins. This technique is used with many studies of Cetaceans (whales, dolphins and porpoises), which all have dorsal fins. As the animals age, their dorsal (back) fins become worn and chipped, which allows individuals to be uniquely identified, much like fingerprints.

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First North American monkey fossils are found in Panama Canal excavation

New species named Panamacebus transitus

Date: April 20, 2016

Source: Smithsonian Tropical Research Institute

Seven fossil teeth exposed by the Panama Canal expansion project are the first evidence of a monkey on the North American continent before the Isthmus of Panama connected it to South America 3.5 million years ago. A team including Carlos Jaramillo, staff scientist at the Smithsonian Tropical Research Institute (STRI), published this discovery online in the journal, Nature today. They named the new monkey species Panamacebus transitus in honor of Panama and the monkey's movement across the ancient seaway that divided North and South America.

The 21 million-year-old teeth were found in the Las Cascadas Formation during a five-year intensive fossil salvage project by field crews from STRI, the University of Florida and the New Mexico Museum of Natural History and Science. Most of the mammal groups represented in the Las Cascadas formation have North American origins, despite the fact that South America is much closer, supporting the idea that Central America and western Panama represented a long peninsula extending south from North America.

During the salvage project, researchers rushed in behind engineers as they dynamited the steep canal banks. The researchers collected exposed fossils and described each location before heavy rains and fast-growing vegetation obscured evidence of the dramatic tectonic events that lifted the land bridge out of the sea to connect North and South America.

"I asked my boss for a million dollars to dig a hole in the ground," said Jaramillo. "Then the Panamanian people voted for the Panama Canal Authority to spend $5.6 billion dollars to expand the Canal and unlocked a treasure trove for us, containing this new monkey species and many other fossils."

"We suggest that Panamacebus was related to the capuchin (also known as "organ-grinder" monkeys) and squirrel monkeys that are found in Central and South America today," said Jonathan Bloch, curator of vertebrate paleontology at the Florida Museum of Natural History on the University of Florida campus and lead author on the study. "Prior to this discovery, New World monkeys were thought to have evolved in isolation on South America, cut-off from North America by a wide seaway."

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Cheetahs migrated from North America

Date:December 8, 2015

Source:BioMed Central

The cheetah (Acinonyx jubatus) is now at home on the African plains, but it started a migration 100, 000 years ago from North America towards its current habitat. The research, published in the open access journal Genome Biology, found that the migration from North America was costly for the species, triggering the first major reduction in their gene pool.

The modern African cheetah is found across eastern and southern Africa, but it is highly endangered because of their small free ranging population and inbreeding. Researchers from St. Petersburg State University, Russia, in collaboration with BGI, China and CCF, Namibia, sequenced the genome from a male Namibian cheetah, called 'Chewbaaka', and six other wild cheetahs from Tanzania and Namibia. This gave further insight into the species evolutionary history and the breadth of genome impoverishment, which elevates juvenile mortality, causes extreme abnormalities in sperm development and increases vulnerability to infectious disease outbreaks.

A total of 18 cheetah genes showed damaging mutations and one gene in particular, AKAP4, showed a large number of mutations, which could harm sperm development and may explain why cheetah have a large proportion of defective sperm, and hence their low reproductive success.

The cheetah is descended from a relative of American pumas and their fossil record extends across the Americas, Europe and Asia. The species has suffered two population bottlenecks -- an event whereby the population is rapidly reduced due to environmental factors.

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North American Mammoths Actually Evolved in Eurasia

by Laura Geggel, Staff Writer   |   November 12, 2015 05:50pm ET

The famous Columbian mammoth — an 11-ton creature known for traversing North America during the last ice age — might actually be the same species as the Eurasian steppe mammoth, a new study finds.

The discovery suggests that the first mammoth to enter North America was the Eurasian steppe mammoth, and not its ancestor, a European creature called Mammuthus meridionalis. The two species differed greatly — the steppe mammoth had many more adaptations to living in cold weather.

The finding helps to rewrite the story of the evolution of the mammoth in North America, said study co-researcher Adrian Lister, a research leader of paleontology at the Natural History Museum in London. 

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Can habitat protection save our disappearing bats?

North America's populations are declining at an unprecedented rate, but research may have found a solution

Date: August 4, 2015

Source: Concordia University

Summary: In summertime, bats are a common feature in the night sky, swooping around backyards to gobble up mosquitoes. Bats also help with crops: they act as a natural pesticide by feeding on harmful insects. But these winged mammals are now under threat. In a new paper, researchers have shown that protecting natural habitats in systems that are highly modified by humans could help struggling bat populations.

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Giant and mini beavers once waddled across North America

June 12, 2015

John Hopton for redOrbit.com – @Johnfinitum

At the time humans arrived, North America was home to some seriously impressive megafauna. Ten thousand years ago, around the period woolly mammoths were dying out, America still had enormous beavers of up to 2 meters (7ft) in length and weighing 200 pounds or more.

The giant beavers, known as Castoroides, closely resembled modern beavers, except they were the size of black bears, had much bigger feet and appear to have had the wrong shaped teeth to cut wood. They therefore probably did not build dams. Aw, dam.

Gizmodo'™s Annalee Newitz suggests that beavers were among the mammals that dealt well with the cooling climate of the Earth during the Pleistocene. The role of humans in their extinction and whether they hunted them is not clear, but it is known that humans hunted woolly mammoths. It’s also possible they were just too afraid to live in a world which had beavers the size of Shaquille O’Neal.

Read more at

Do Not Fear the Sailor 'Jellyfish' Invasion

By Cathy Lucas, University of Southampton | October 05, 2014 07:17pm ET

This article was originally published on The Conversation. The publication contributed this article to Live Science's Expert Voices: Op-Ed & Insights.

Billions of small, jellyfish-like creatures known as “by-the-wind sailors” have washed ashore all along the west coast of North America this summer, from southern California to British Columbia. Images of vast swarms of electric-blue sails covering the ocean’s surface and littering the sand are indeed spectacular, but people might well wonder what exactly these strange-looking beings actually are. And this of course leads to the next question – should we be afraid of them?

Velella velella (to give them their scientific name) are often assumed to be a type of jellyfish but, while biology does lump them in with jellyfish, sea anenomes, and corals in a group known as Cnidaria, Velellas are not all that closely related to the common or moon jellyfish, Aurelia aurita.

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Starfish deaths off US coasts continue to puzzle scientists

Researchers rule out culprits including fungi and certain parasites, but remain vexed by unexplained wasting disease

theguardian.com, Friday 2 May 2014 15.08 BST

Scientists are struggling to find the cause of a disease that is killing off numerous species of starfish on both the Pacific and Atlantic coasts of North America, dispatching the five-armed creatures in a particularly gruesome way.

Researchers said this week that they have ruled out some possible culprits including fungi, some parasites and certain other microorganisms and are taking a hard look at whether viruses or bacteria may be to blame.

The starfish, also called sea stars, are being obliterated by an unexplained wasting disease that causes white lesions to appear before the animal's body sags and ruptures and it spills out its internal organs.

"The magnitude of it is very concerning. There's the potential that some of these species could actually go extinct," said Cornell University ecologist Drew Harvell, one of the scientists involved in the loosely organised search for a cause.

Harvell said she is concerned because the mysterious pathogen is affecting 18 different west coast species along their entire range. Pathogens that affect an animal's range in such a way like a fungus that has targeted frogs can be particularly damaging, she said.

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North American Monarch Butterfly Protection Urged By 150 Intellectuals

MEXICO CITY (AP) — Dozens of scientists, artists, writers and environmentalists on Friday urged the leaders of Mexico, Canada and the United States to devote part of their meeting next week to discussing ways to protect the Monarch butterfly.

A letter to the three leaders signed by more than 150 intellectuals, including Nobel literature laureate Orham Pamuk, U.S. environmentalist Robert Kennedy Jr. and Canadian author Margaret Atwood , notes the Monarch population has dropped to the lowest level since record-keeping began in 1993.

Mexican President Enrique Pena Nieto, U.S. President Barack Obama and Canadian Prime Minister Stephen Harper Obama are meeting in Toluca, near Mexico City, on Wednesday to discuss such matters as economic competitiveness, trade and investment, entrepreneurship and security.

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Oldest and Youngest Stag-Moose in North America

Sep. 19, 2013 — Matthew Hill has identified countless bones found by farmers, fishermen, rock hounds and heavy equipment operators. Most of the remains turn out to be deer, bison, horse or cow bones, or simply odd looking rocks. But some discoveries turn out to be highly unusual, as was the case with an antler from an extinct Ice Age animal known as a stag-moose or elk-moose.

"At first, I was puzzled. I knew it did not belong to a white-tailed deer, elk or caribou. It looked sort of like a moose antler, but not quite -- it was different," Hill said. "I suspected it might be stag-moose, so I sent a picture to a colleague at the Illinois State Museum to compare it with specimens in their collections. He confirmed my suspicion."

The discovery inspired Hill, an associate professor of anthropology at Iowa State University, to learn more about when the animal was in Iowa and search for additional specimens. Specifically, he wanted to determine the age of the antler and two other specimens he located. So he carefully cut a small cube from each specimen and sent them off to an Arizona lab for radiocarbon dating.

The results far exceeded Hill's expectations. Turns out, one of the samples is more than 30,000 years old, making it the oldest specimen of a stag-moose ever recorded in North America. The results of the radiocarbon dating, which would not have been possible without a grant from the College of Liberal Arts and Sciences, are now fueling Hill's curiosity and new research.

"It means that these animals were here before the glaciers covered central Iowa, and that they returned for a short time after the glaciers retreated as well," Hill said. "Still, we don't know a whole lot about the ecology of these animals. When they appeared, their numbers on the landscape, the cause of their demise, and what other animals they were living with side-by-side? There are just a whole lot of questions and this will be a great opportunity to learn more."

Such discoveries often start with a phone call. Hill fields dozens of calls each year from people across the state with questions for him about a bone or a skull. In fact, the stag-moose antler that sparked Hill's interest was discovered by an Ames man, who was searching the South Skunk River near Ada Hayden Park for remains. Radiocarbon dating determined the antler to be 13,400-13,700 years old.

The 30,000-year-old specimen was found in the 1970s by a gravel pit operator working near Jester Park in Polk County. It was donated to the State Historical Museum in Des Moines, where it is on display. The third specimen, located near Parkersburg, is part of a personal collection. Hill said the animal lived 12,600 to 12,800 years ago, and tied a specimen from north-central Wisconsin for the youngest record of the stag-moose. What he finds most exciting is that the age of the Parkersburg specimen suggests the first people to occupy Iowa -- so-called Clovis hunters -- may have preyed on the beast.

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