It wouldn’t have been the easiest way to get around. A University of Alberta paleontologist has helped discover the existence of a 95 million-year-old snakelike marine animal, a finding that provides not only the earliest example of limbloss in lizards but the first example of limbloss in an aquatic lizard.

Close-up of Adriosaurus microbrachis.

A University of Alberta paleontologist has helped discover the existence of a 95 million-year-old snakelike marine animal, a finding that provides not only the earliest example of limbloss in lizards but the first example of limbloss in an aquatic lizard.

“This was unsuspected,” said Dr. Michael Caldwell, from the U of A’s Faculty of Science. “It adds to the picture we have of what was happening 100 million years ago. We now know that losing limbs isn’t a new thing and that lizards were doing it much earlier than we originally thought. On top of that, this lizard is aquatic. All the examples we have in our modern world are terrestrial, so it’s a big deal.”

The evidence offers the earliest record of vestigial limbs–once used in an animal’s evolutionary past but that has lost its original function– in a fossil lizard. The newly named species–Adriosaurus microbrachis–is described in the current issue of the Journal of Vertebrate Paleontology and offers clues to the evolution of terrestrial lizards as they returned to water.

The fossil was originally collected during the 19th Century from a limestone quarry in Slovenia. It then sat at the Natural History Museum in Trieste, Italy for almost 100 years before Caldwell and a colleague found it in 1996 during a trip to Europe. He later connected with Alessandro Palci, then a graduate student in Italy whom he helped supervise, and they worked on the fossil together.

The researchers soon realized the lizard’s front limbs were not formed during development. “There was a moment when I said, ‘I think we stumbled on a new fossil illustrating some portion of the aquatic process of losing limbs,’” said Caldwell. “There are lots of living lizards that love to lose their forelimbs and then their rearlimbs, but we didn’t know it was being done 100 million years ago and we didn’t know that it was happening among groups of marine lizards.”

The researchers think this snake-like lizard was about 10 to 12 inches long, had a small head perched on an elongated neck, body and tail and relatively large and well-developed rear limbs. All bones of the forearm, including the hands and digits were not formed during development.

“For some oddball reason the forelimbs were lost before the rear limbs when you would think it would be the opposite,” said Caldwell. “The front limbs would be useful for holding onto dinner or digging a hole but it must be developmentally easier to get rid of the forelimbs.”

The most well known ancient fossil snakes also kept their hind limbs. Living lizards also show almost every variation in limb reduction from a perfectly formed back limb with no forelimb, or a spike for a forelimb and one or two toes on the rearlimb, to total limblessness. This degree of variation makes it very difficult to understand the pattern of evolutionary limb loss in these animals.

“This discovery is one more data point that might help us answer some questions and perhaps shed some light on the fin to limb transition, which is a key step in the evolution of land animals,” said Caldwell. “It doesn’t give us all the answers but it’s a start.”

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A research team led by San Jose State University and the University of California, Santa Barbara has discovered forests of a species of kelp previously thought endangered or extinct in deep waters near the Galapagos Islands.

Marine iguana feeding in area of kelp forest.

The discovery has important implications for biodiversity and the resilience of tropical marine systems to climate change.

“The ecosystems that form in these cold, deep pockets beneath warm tropical waters look more like their cousins in California than the tropical reefs just 200 feet above,” said co-author Brian Kinlan, a researcher with UC Santa Barbara’s Marine Science Institute. “It is very similar to what we see when we climb a high mountain. For example, high alpine country in California looks more like Alaska.”

Kinlan and Michael Graham, associate professor at SJSU, began by developing a mathematical model designed to predict likely habitat for the kelp, Eisenia galapagensis, based on information from satellites and oceanographic instruments on conditions including light, depth and nutrient availability. The premise of the model was developed by collaborator Louis Druehl, of the Bamfield Marine Science Centre, who surmised it was possible to create a predictive model for locating kelp forests rather than focusing on the limited details available from rare field observations.

The research team tested the model by traveling to the predicted habitat, where they searched for the kelp. Scuba divers — including students from CSU Monterey Bay, CSU East Bay and UC Davis — found the kelp forests from 40 to 200 feet below the surface, making the mission a success. The students conducted their surveys alongside the famed Amblyrhynchus christatus, the world’s only seagoing iguanas.

The mission’s success has three major implications. First, the World Conservation Union, which recently added Eisenia galapagensis to its global database of threatened species, may reconsider that action. Second, the model may find other marine life presumed endangered or rare but actually hidden beneath the ocean’s surface.

The model does this by pinpointing unexpected places to search. In this case, the model correctly predicted that deep waters in the tropics could harbor kelp forests more commonly associated with temperate regions such as central California. The model identified nearly 10,000 square miles of similar unexpected cold spots in deep tropical waters worldwide.

The third implication of the research is that marine biodiversity may be more tolerant of climate change than presumed. Graham compares his team’s kelp forests to the underwater hydrothermal vents discovered off South Africa in 1977. Scientists were surprised to find thriving ecosystems near those vents in water previously considered too deep and dark to harbor complex communities.

Graham theorizes the kelp forests his team discovered may reveal a similar wealth of plant and animal life. So while global warming may heat coral reefs and alter life there, marine communities may continue to thrive in kelp forests deep beneath the surface, where cooler nutrient-rich waters are less affected by surface warming.

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World Wildlife Fund scientists have just announced the discovery of 11 new animal and plant species in a remote area in central Vietnam. They say this underscores the importance of conservation efforts in the ancient tropical forests of the region.
Gastrodia theana — A very rare leafless orchid discovered in Vietnam.

Within the ancient tropical forests of a region known as Vietnam’s “Green Corridor,” scientists found a snake, five orchids, and two butterflies as well as three other plants new to science and exclusive to the Annamites Mountain Range. Ten other plant species, including four orchids, are still under examination but also appear to be new species.

“Discoveries of so many new species are rare and occur only in very special places like the Green Corridor,” said Dr. Chris Dickinson, WWF’s chief conservation scientist in the Green Corridor. “Several large mammal species were discovered in the 1990s in the same forests so these latest discoveries may be just the tip of the iceberg.”

The rainforests of the Central Annamites likely existed as continuous undisturbed forest cover for thousands of years, and, as a result, offer unique habitats for many species, said WWF experts.

The new snake species, called the white-lipped keelback, prefers living by streams where it catches frogs and other small animals. With a beautiful yellow-white stripe sweeping along its head and red dots covering its body, the white-lipped keelback can reach 31 inches–almost a yard in length.

Three of the new orchid species are entirely leafless, a rarity even among orchids. Containing none of the chlorophyll or green pigment commonly found in plants, these orchids live on decaying matter like many fungal species. The other new plants include an aspidistra which produces a nearly black flower and a newly-discovered species of arum with beautiful yellow flowers. Arum plants have funnel-shaped leaves surrounding the flowers.

The two new butterfly species are among eight discovered in the province since 1996. One is a skipper — a butterfly with quick, darting flight habits–from the genus Zela and the other is a new genus in the subfamily of Satyrinae.

According to WWF experts, all of these species are at risk from illegal logging, hunting, unsustainable extraction of natural resources and conflicting development interests. However, local authorities — in particular the Thua Thien Hue Provincial Forest Protection Department — have committed to conserve and sustainably manage these valuable forests.

“The area is extremely important for conservation and the province wants to protect the forests and their environmental services, as well as contribute to sustainable development,” said Hoang Ngoc Khanh, director of Thua Thien Hue Provincial Forest Protection Department.

Stretching from the mountainous forests of the Annamites to one of the last remaining lowland wet evergreen forests, the Green Corridor supports significant populations of threatened species and includes some of the longest remaining stretches of lowland river with intact forest habitat in Vietnam feeding into the Perfume River.

Recent surveys found 15 reptiles and amphibians and six bird species among the threatened species living there. It is also home to one of the world’s most endangered primates–white-cheeked crested gibbons–and the best location in Vietnam to save the saola–a unique type of wild cattle just discovered by scientists in 1992.

According to WWF experts, the forests of the Annamites are important water catchments, supplying water for thousands of people who depend on the region’s rivers. Local ethnic minority groups earn more than half of their income from the non-timber resources of these same forests.

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