About Animals / Wildlife

Fossil Primate Hints at Asian Anthropoid Origin

2009-07-05T19:19:35Z

A new fossil primate has been reported by paleontologist K. Christopher Beard of the Carnigie Museum of Natural History. The new fossil, which is referred to by the nickname Ganlea, was discovered in Myanmar in 2005 and suggests that early anthropoids originated in Asia. This contradicts the theory that anthropoid origins are rooted in Germany, as suggested by the scientific team that found Ida.

Seagrass Meadows Under Threat

2009-07-05T18:38:01Z

Seagrass meadows around the globe are disappearing at an alarming rate. A team of scientists led by by Michelle Waycott of James Cook University in Townsville, Queensland, Australia analyzed data for seagrass habitats around the globe that were gathered between 1879 and 2006. They found that in the 215 sites they looked at, the area of known seagrass meadow habitat fell by 29 percent during that time period.

Saving the Large Blue Butterfly

2009-07-02T09:26:29Z

A striking cobalt-blue butterfly from the United Kingdom is making headlines as a conservation success story. The large blue butterfly (Maculinea arion) disappeared from Great Britain in 1979 and remained locally extinct until 1983 when scientists imported large blue butterflies from Sweden in an effort to revive the former British population.

The team of scientists that reintroduced the large blue butterfly to Britain has now published a paper detailing 40-years of meticulous observations that they complied on the species. The long-term study, led by Jeremy Thomas of Oxford University, represents a landmark in conservation science—little is known of how to successfully protect rare invertebrates and the findings for the large blue butterfly provide a superb example of invertebrate conservation.

The large blue butterfly is a globally threatened lepidopteran species. Its current range extends across northern Spain, Italy, Greece, and southern Scandinavia. In the UK, the species was estimated to consist of 91 colonies from the late 1790s to the 1840s. But in the 1950s, only 25 popluations remained and in 1972 only two colonies remained. Those two colonies became extinct in 1979.

Maculinea arion has a complex life cycle and requires a very specific type of habitat. The species prefers areas with grasses and wildflowers, especially those that include thyme (Thymus) species. Adult female large blue butterflies lay their eggs on thyme flowers in the summer (June–July). When the eggs hatch, the young caterpillars feed on the flower heads of the thyme plant for about three weeks before dropping to the ground. That's when the Maculinea life cycle takes an odd turn.

The caterpillar secretes chemicals that mimic those of ant larvae, so when a worker ant (either Myrmica sabuleti or Myrmica scabrinodis) comes across the caterpillar, it takes it back to its underground nest where the ant colony cares for the caterpillar as one of its own. Thus the large blue butterfly caterpillar acts as a parasite to the unsuspecting ant host species for 10 months, after which time the large blue butterfly caterpillar enters the pupal stage. Two to three weeks later, the large blue emerges as an adult butterfly.

The key to conserving the large blue butterfly in the UK was understanding the primary cause of its decline. But for a long time, no one really knew why the large blue was disappearing. What Thomas and his colleagues discovered was that seemingly small changes in its habitat were having disastrous consequences for the success of large blue butterfly populations. They noted that when caterpillars were adopted by their primary ant host species, Myrmica sabuleti, they survived far better than when adopted by their secondary host ant host species, Myrmica scabrinodis. Yet when the grass in their habitat was long (greater than 1.4 cm tall) the secondary host ant host species, Myrmica scabrinodis took over most of the habitat while the primary ant host species, Myrmica sabuleti became rare.

This meant that large blue butterfly caterpillars were far less successful and as a result the population of the butterflies declined consistently until the entire UK population went extinct. In 1983, Jeremy Thomas and his colleague put their knowledge of caterpillar success, ant species, and grass height to work. They took what they had learned of the large blue butterfly, its habitat, and its host species and created the ideal habitat for the large blue butterfly. Then they set off to Sweden to captured some large blue butterflies–individuals that would serve as founders of a new colony— and transported them to the UK where they set them free into a number of restored habitat sites. By 2008, the butterfly population had blossomed to include 30 percent more colonies than were present in the 1950s.

Refs: Thomas, J., Simcox, D., & Clarke, R. (2009). Successful Conservation of a Threatened Maculinea Butterfly Science DOI: 10.1126/science.1175726

Photos © David Simcox / Centre for Ecology and Hydrology, UK.

Debating Our Closest Cousins

2009-06-28T22:51:57Z

Scientists Jeffrey Schwartz of the University of Pittsburgh in Pennsylvania and John Grehan of the Buffalo Museum of Science in New York recently published a paper that give the human evolutionary branch and its neighbors a good shake-up. The new research suggests that humans are more closely related to orang-utans than they are to chimpanzees and in doing so flies in the face what has for some time been a well-accepted phylogenetic arrangement.

Dazzling Photos Depict Darwin's Creatures

2009-06-27T00:33:14Z

The Guardian has put together a wonderful gallery of images depicting some of the animals that Charles Darwin studied. The pictures include creatures such as barnacles, beetles, tortoises, mockingbirds, and many others.

Darwinfest Podcasts from Arizona State University

2009-06-24T16:44:35Z

Arizona State University has a wonderful program commemorating the 150th anniversary of the publication of On the Origin of Species and the 200th anniversary of the birthday of its distinguished author, Charles Darwin. The program, Darwinfest: Bold Ideas Change Worlds, features a series of podcasts and videos on a range of topics including:

Darwin and the Future of Biology by Edward O. Wilson (mp3 | iTunes)
Exploring the Superorganism by Bert Hölldobler (mp3 | iTunes)
Don't Be Such a Scientist by Randy Olson (mp3 | iTunes)
Is Darwinisim Past its Sell-By Date? by Michael Ruse (mp3 | iTunes)
On the Origin of Our Species: Darwin and Human Evolution by Bernard Wood (mp3 | iTunes)

So sync-up your mp3 player and get a good dose of Arizona State University's Darwinfest!

New Explanation for Fossil-Rich Bone Bed

2009-06-21T22:30:15Z

Just outside of Bakersfield, California lies a remarkable fossil bed that stretches over an area of 50 square miles. The site, known as Sharktooth Hill Bone Bed, was discovered in the 1850s and has yielded a surprising diversity of fossils—ancient seals, sea turtles, dolphins, whales and sharks. The bone deposits within Sharktooth Hill are so dense they form an earthen layer that varies in thickness from six to 20 inches.

Experts have long debated how such a concentrated collection of bones were preserved at this single location. One proposed explanation is that the Sharktooth Hill was a killing ground for megalodon, a 40-foot shark that roamed the seas around 15 million years ago. Another explanation suggests the site was a long-time breeding grounds for seals and other marine mammals.

Now, a team of paleontologists from University of California, Berkeley, the University of British Colombia, Vancouver, and the University of Utah have suggested yet another possible explanation for the bones at Sharktooth Hill. The researchers propose that the bone bed records a 700,000-year period between 15 and 16 million years ago when normal life and death cycles in the region were preserved under unusual climate conditions.

At the time Sharktooth Hill Bone Bed formed—between 15,900,000 and 15,200,000 years ago—California's Central Valley lay beneath an inland sea known as the Temblor Sea. Many of the bones collected from Sharktooth Hill were scattered as if they had been moved by water currents. As one scientist from the UC Berkeley team described:

"The bones look a bit rotten, as if they lay on the seafloor for a long time and were abraded by water with sand in it," ~ Jere Lipps, University of California, Berkeley.

The research team suggests that Sharktooth Hill formed during a period of 100,000 to 700,000 years when the Temblor Sea was choppy enough to prevent sediments from settling. As a result, the bones collected on the seafloor where they were churned about and formed a large underwater pile of remains.

Find out more: Fossil bone bed helps reconstruct life along California's ancient coastline

Photo © Nick Pyenson / University of British Columbia.

What is a Species?

2009-06-18T23:02:51Z

The term species can be defined as a group of individual organisms that are capable of interbreeding to produce fertile offspring in nature. A species is, according to this definition, the largest gene pool that exists under natural conditions. Thus, if a pair of organisms are capable of producing offspring in nature, they must belong to the same species.

Fossil Horse Teeth Salvaged from Panama Canal Worksite

2009-06-12T11:08:39Z

Aldo Rincon, a paleontology intern working with the Smithsonian Tropical Research Instituted, recently unearthed the fossil remains of an ancient three-toed horse from a building site alongside the Panama Canal. The fossil was collected as part of an effort that is underway to salvage fossils as the canal is widened.

The fossil teeth belong to a previously known species of horse, Anchitherium clarenci, a forest-dwelling species that lived in the region between 15 and 18 million years ago. Fossil remains of Anchitherium clarenci had previously been found in Florida, Nebraska, and South Dakota. This latest discovery extends the southern limit of the species' range during that time period.

The widening of the 48-mile Panama Canal will enable large ships to pass through the isthmus. To date, 10 million cubic meters of earth have been removed from the banks of the canal. Scientists and students from the Smithsonian Tropical Research Institute, the Panama Canal Authority, and the University of Florida have joined forces to examine sites exposed by dynamite blasts and collect and catalog any fossil in those areas. Despite controversy over the ecological impacts the widening of the canal brings, paleontologists are excited for the opportunity to collect fossils from the region:

"This is one of very few places in the tropics where we have access to fresh outcrops before they are washed away by torrential rains or overgrown by vegetation, and we expect the fossils that we have been salvaging to resolve some major scientific mysteries. What geological forces combined to create the Panama land bridge? Was the flora and fauna in Panama before the land bridge closed similar to that in North America, or did it include other elements?" ~ Carlos Jaramillo.

Refs: Fossil Teeth of Browsing Horse Found in Panama Canal Earthworks (Eurekalert)

Animal ID Challenge - Marine Iguana, Galapagos Land Iguana, or Komodo Dragon

2009-06-11T11:20:11Z

In today's animal identification challenge, we have a rather unique reptile. This creature is the largest of all lizards. Adults of the species can grow to lengths of 3 m and can weigh as much as 165 kg. It is the top carnivore in the ecosystem it inhabits and feeds on carion as well as a variety of large mammals such as deer, wild boar, horses, and water buffalo. Its mouth is equipped with a long, yellow, deeply-forked tongue and sharp serrated teeth. Until recently, scientists thought this lizard's saliva was laden with pathogenic bacteria that infected and immobilized its prey. But now, there is clear evidence that this lizard is venomous and innoculates its prey with a potent cocktail of toxins that cause debilitating pain and shock.

This species is an island-dwelling creature whose prefered habitats include tropical savannah forests, open lowland habitat, beaches, and dry riverbeds.

Your task is to identify which of the following three lizards this species belongs to: marine iguana, Galapagos land iguana, or Komodo dragon.

After you have cast your vote in this Animal ID Challenge, be sure to check your answer here.