Naturalist Alfred Wallace on the Internet

This video is called Operation Wallacea – Indonesia schools expedition.

From Wildlife Extra:

Historic collection of naturalist Alfred Wallace goes online for the first time

Treasure-trove of writings and images by the co-discoverer of natural selection

October 2012. The complete works of the great naturalist Alfred Russel Wallace have been made freely available online on the Wallace Online website.

First announcement of the theory of evolution by natural selection

Amongst the thousands of pages of writings, it includes the first announcement of the theory of evolution by natural selection.

Wallace and Darwin

Since the scientist’s death 99 years ago, Wallace’s complete publications have never been gathered together. The new website is unveiled in time for the centenary celebrations in 2013 that mark the anniversary of Wallace’s death in 1913.

Back in the 1850s, Wallace independently formulated the theory of evolution by natural selection during a fit of tropical fever. He later sent an outline of the theory – in one of the greatest ironies in history – to Charles Darwin. To avoid a priority dispute, papers by both men were read together at a London scientific meeting in July 1858. The event unleashed the Darwinian revolution whose shockwaves continue to this day.

Wallace has long been in the shadow of his more famous contemporary Charles Darwin. The compilation of this new website is timely and long overdue. It provides 28,000 pages of searchable historical documents and 22,000 images. They can now be seen free of charge by anyone around the globe at Wallace Online.

Wallace’s contributions to biodiversity

Wallace spent four years as a collector in Brazil (1848-1853) and eight years in Southeast Asia (1854-1862). In addition to collecting an astonishing 125,000 specimens of insects and birds, Wallace proposed a sharp dividing line between the Asian and Australian animals in the archipelago. This line still bears his name today and is called The Wallace Line.

One of the most influential scientists in history

Dr van Wyhe, project director, said: “Wallace was one of the most influential scientists in history. But until now, it has been impossible to see all of his writings. For the first time, this collection allows anyone to search through his writings about Singapore, Malaysia and Indonesia, and see many of the birds and insects that he collected.”

Dr van Wyhe holds a joint appointment as Senior Lecturer at NUS’ Department of Biological Sciences and the Department of History, under Faculty of Science and Faculty of Arts and Social Sciences, respectively. He is also the founder and director of the award-winning Darwin Online at the University of Cambridge, UK.

This project was directed by historian Dr John van Wyhe from the National University of Singapore (NUS). The Wallace Online project was made possible by an anonymous grant from an American donor.

Asian trees and ‘flying’ lizards evolution

This is a video about “flying” frogs.

From New Scientist:

Tall trees may have sparked evolution of gliding

15:56 20 September 2012 by Jeff Hecht

The gliding animals of south-east Asia have something in common with the Himalayas. Both owe their existence to the collision of India with Eurasia around 50 million years ago. In the wake of the continental clash, tall tropical trees spread from the subcontinent and began to dominate Asian rainforests, providing a perfect environment for the evolution of gliding.

South-east Asia’s rainforests are famed for their exceptional variety of gliders. Geckos, Draco lizards, flying squirrels, colugos and frogs have all taken to the skies, suggesting the adaptation evolved several times in the region. Now a study by Matthew Heinicke at the University of Michigan at Dearborn and colleagues has found evidence to support a link between the adaptation and the forests’ unusual vegetation, which is dominated by dipterocarps – trees that grow unusually tall and typically mature to lack any branches on the lower 30 metres of their trunks.

“It makes more energy sense for a small animal to glide between trees than to climb all the way down one tree and then climb back up another,” says Heinicke.

Heinicke and his colleagues looked at the evolutionary history of the animal groups that contain one or more gliding species. Their analysis suggests that gliding evolved independently eight times in the forests, and that six of those evolutionary events occurred between 20 million and 50 million years ago – the time during which dipterocarp trees were first able to spread from India across southeast Asia.

A seventh group, Draco lizards, split earlier from its non-gliding relatives – perhaps as early as 60 million years ago – pre-dating the collision of India with Eurasia. These lizards evolved in India, however, and so may still have begun to glide in dipterocarp-dominated forests. The eighth group – the colugos – apparently split from non-gliding primates nearly 80 million years ago, making them an exception to the theory.

“Conceptually, it’s really clever what they have done,” says palaeontologist David Hone at the University of Bristol, UK.

The evolution of gliding by four-legged tree climbers was probably a key step on the path to flight for bats and pterosaurs, although none of the gliders in the modern dipterocarp forests are closely related to these active flyers.

Birds, though, may have taken another route to the skies, says Michael Habib of the University of Southern California in Los Angeles. They evolved from feathered dinosaurs like the four-winged Microraptor, which looks like it could have run bipedally on the ground, says Habib.

Scottish flower evolution discovery

Not only evolution in action among starfish, but among flowers as well …

From SINA English in China:

Newfound monkey flower reveals evolution in action

2012-07-18 09:30:20 GMT2012-07-18 17:30:20(Beijing Time)

A new species of monkey flower has been found in Scotland,

This music video is called Flower of Scotland ~Lone Piper~ Bagpipes.

the product of a tryst between two foreign flowers. But this is no ordinary love child. While almost all such hybrids are sterile — just as mules are sterile hybrids of donkeys and horses — a rare genetic duplication allowed this species to become fertile.

It’s rare to discover a newly evolved species, said researcher Mario Vallejo-Marin, who found the handsome yellow flower while on a walk through southern Scotland with his family last summer.

While many new species of plants are thought to arise this way, it has only been witnessed amongst wild plants a handful of times in history, said Vallejo-Marin, a scientist at the University of Stirling. Hybrid flowers typically have an odd number of chromosomes, or enormous packets of DNA, making them unable to reproduce. But this flower somehow duplicated its entire genome.

Vallejo-Marin said he doesn’t know exactly what “series of unlikely events” led to this new species, but he said he intends to study it in more detail. Insights could help explain how these new hybrids regain fertility, which could also shed light on the evolution of plants such as wheat, tobacco and cotton, which are thought to have evolved this way long ago.

“It provides an opportunity to study speciation as it happens —most species originated thousands of years ago,” and so studying their evolution is harder, Vallejo-Marin told OurAmazingPlanet.

The new species — Mimulus peregrines,

This article and others on the Internet have the spelling wrong. It is Mimulus peregrinus.

or “the wanderer” — is unique because it has a different-size genome than any other monkey flower and cannot reproduce with any other variety, according to the study describing the find, published in the June edition of the journal PhytoKeys.

The “parents” of the new species were spirited to Scotland from the western United States and South America’s Andes Mountains in the 1800s. The new species arose 140 years ago at the most, but more likely came about in the last few decades, Vallejo-Marin said.

Monkey flowers are named for the shape of their attractive blooms, which with some imagination, resemble the face of an ape. “If you ask me, it doesn’t look like that, but the name stuck,” Vallejo-Marin said.

The ancestors of the new plant were sought after as botanical curiosities in the 1800s and were quickly adopted by Victorian gardeners. Soon after their arrival, they escaped the confines of British gardens and can now be found growing in the wild, along the banks of rivers and streams.

(Agencies)

Scientists advance understanding of how flowers are formed: here.

Evolutionary molecule identified by researchers: here.

Sea star evolution discovery

This video is called Starfish Eating.

From the Hawaii Institute of Marine Biology:

Researchers discover fastest speciation for marine animals

Wednesday, 18 July 2012, 10:58 am

Researchers at the Hawai‘i Institute of Marine Biology (HIMB), an organized research unit in the University of Hawai‘i at Mānoa’s School of Ocean and Earth Science and Technology in an international collaboration with University of California at Davis, Simon Frasier University and the University of Sydney have made a remarkable new discovery.

Understanding the processes that create and maintain biodiversity, such as when and how new species form, remains one of the greatest challenges facing biologists, conservation scientists, and managers today. These processes are especially obscure in the ocean, where many organisms have tiny juvenile larval stages that swim in the plankton for some time before settling into a largely sedentary adult. This larval stage has the potential to disperse over great distances and keep populations very well-mixed, thus decreasing the chance for speciation. On the other hand, larvae also have the opportunity to disperse great distances to colonize new habitats where they may adapt and perhaps even evolve into a new species. This process usually takes hundreds of thousands to millions of years.

In a new study released today, researchers discovered that two species of sea stars evolved only 6,000 years ago, during a period of rapid environmental alteration. In the process, one species changed from the ancestral form with separate sexes that release eggs into the water for fertilization. The new species, Cryptasterina hystera, lost the planktonic larval stage all together, and changed from having separate sexes to being hermaphroditic (organisms that have both sexes). This species now carries juveniles internally until they give birth to live young, and has the potential to self-fertilize. This shift in reproduction has dramatically reduced the genetic diversity of C. hystera to levels that are on par with many endangered species. Additionally, populations of this species are genetically different among tide pools only meters apart from each other. This rapid speciation in response to environmental change means that some may have the potential to adapt to future climate change. Postdoctoral researcher, Jon Puritz led the investigation, and when asked about the recent discovery said, “This rate of speciation is nearly a hundred times faster than we normally see in the ocean, and to have it coupled with such a drastic change in life history is really spectacular. It seems like evolution in life history traits may be a particularly fast pathway to speciation.”

The Royal Society journal Proceedings of the Royal Society B has published the full research report by Puritz et al. and is available here.

Galapagos tortoise Lonesome George dies

This video is about the Galapagos islands and the tortoise Lonesome George.

From the BBC:

24 June 2012 Last updated at 22:25 GMT

Last Pinta giant tortoise Lonesome George dies

Staff at the Galapagos National Park in Ecuador say Lonesome George, a giant tortoise believed to be the last of its subspecies, has died.

Scientists estimate he was about 100 years old.

Park officials said they would carry out a post-mortem to determine the cause of his death.

With no offspring and no known individuals from his subspecies left, Lonesome George became known as the rarest creature in the world.

For decades, environmentalists unsuccessfully tried to get the Pinta Island tortoise to reproduce with females from a similar subspecies on the Galapagos Islands.

Park officials said the tortoise was found dead in his corral by his keeper of 40 years, Fausto Llerena.

While his exact age was not known, Lonesome George was estimated to be about 100, which made him a young adult as the subspecies can live up to an age of 200.

Galapagos icon

Lonesome George was first seen by a Hungarian scientist on the Galapagos island of Pinta in 1972.

Environmentalists had believed his subspecies (Chelonoidis nigra abingdoni) had become extinct.

Lonesome George became part of the Galapagos National Park breeding programme.

After 15 years of living with a female tortoise from the nearby Wolf volcano, Lonesome George did mate, but the eggs were infertile.

He also shared his corral with female tortoises from Espanola island, which are genetically closer to him than those from Wolf volcano, but Lonesome George failed to mate with them.

He became a symbol of the Galapagos Islands, which attract some 180,000 visitors a year.

Hunted to extinction

Galapagos National Park officials said that with George’s death, the Pinta tortoise subspecies has become extinct.

They said his body would probably be embalmed to conserve him for future generations.

Tortoises were plentiful on the Galapagos islands until the late 19th century, but were later hunted for their meat by sailors and fishermen to the point of extinction.

Their habitat furthermore suffered when goats were introduced from the mainland.

The differences in appearance between tortoises from different Galapagos islands were among the features which helped the British naturalist Charles Darwin formulate his theory of evolution.

Some 20,000 giant tortoises of other subspecies still live on the Galapagos.

See also here. And here. And here.

The rarest animal in the world is no more. Lonesome George, the last of the Pinta Island tortoises, was found dead on Sunday. But a small hope remains for his subspecies, as its genes have survived: here.

Giant tortoise death casts shadow over Galapagos Islands: here.

Evolution in New York City

From The Loom blog in the USA:

Last summer I wrote in the New York Times about the exploits of Jason Munshi-South, a biologist who studies evolution in the wilds of New York City. Jason has now given a nice quick talk for TED-ED, TED’s new educational project, which is illuminated with lovely animations. Check it out:

Gymnosperm and flowering plant evolution

This video is called Seed Production in Gymnosperm.

From New Phytologist journal:

Cenozoic extinctions account for the low diversity of extant gymnosperms compared with angiosperms

Michael D. Crisp,
Lyn G. Cook

Article first published online: 6 SEP 2011

Summary

•
We test the widely held notion that living gymnosperms are ‘ancient’ and ‘living fossils’ by comparing them with their sister group, the angiosperms. This perception derives partly from the lack of gross morphological differences between some Mesozoic gymnosperm fossils and their living relatives (e.g. Ginkgo, cycads and dawn redwood), suggesting that the rate of evolution of gymnosperms has been slow.
•
We estimated the ages and diversification rates of gymnosperm lineages using Bayesian relaxed molecular clock dating calibrated with 21 fossils, based on the phylogenetic analysis of alignments of matK chloroplast DNA (cpDNA) and 26S nuclear ribosomal DNA (nrDNA) sequences, and compared these with published estimates for angiosperms.
•
Gymnosperm crown groups of Cenozoic age are significantly younger than their angiosperm counterparts (median age: 32 Ma vs 50 Ma) and have long unbranched stems, indicating major extinctions in the Cenozoic, in contrast with angiosperms. Surviving gymnosperm genera have diversified more slowly than angiosperms during the Neogene as a result of their higher extinction rate.
•
Compared with angiosperms, living gymnosperm groups are not ancient. The fossil record also indicates that gymnosperms suffered major extinctions when climate changed in the Oligocene and Miocene. Extant gymnosperm groups occupy diverse habitats and some probably survived after making adaptive shifts.

Fern evolution

From ScienceDaily:

Ferns Took To The Trees And Thrived

(July 2, 2009) — As flowering plants like giant trees quickly rose to dominate plant communities during the Cretaceous period, the ferns that had preceded them hardly saw it as a disappointment.

In fact, they flourished. While modern tropical rain forests were becoming established, ferns climbed aboard, and experienced a flowering of their own species diversity.

“The canopy is there and — boom — diversification,” said Duke University researcher Eric Schuettpelz, who is completing a post-doctoral fellowship in biology with associate professor Kathleen Pryer.

By integrating genomic data from 400 living fern species with information from the fossil record, Schuettpelz and Pryer constructed a new time-calibrated family tree for ferns. Their study appears on the cover of the July 7 Proceedings of the National Academy of Sciences.

Though ancient, it appears that ferns really came into their own during a very hot, very wet period that peaked about 10 million years after the Cretaceous/Tertiary boundary 65 million years ago.

Two key innovations may have led to the ferns’ success in the face of the new competition from flowering plants, Schuettpelz said. Some ferns developed the ability to make a living on light that was more toward the red end of spectrum — shade, in other words. And, around this time, some ferns also developed the ability to live on trees, sometimes without soil, as epiphytes.

By storing water, developing thicker skin, or being more tolerant to drying out, the epiphytic ferns could now perch on a trunk, limb, or twig and live quite happily more than 100 feet off the forest floor, where moisture, temperature, and sunlight are very different indeed.

Whereas the fossil record seemed to suggest that ferns experienced three distinct pulses of species diversification, the Duke team’s analysis shows that there was a fourth, roughly corresponding with the development of epiphytism.

So, as rain forests developed and tropical trees and vines clawed past each other to reach heavenward, they took the ferns up along with them. Thousands of new fern species evolved to take advantage of all the new niches being created in the canopy.

“In some ways I guess, the epiphytes escaped the battle on the ground,” Schuettpelz said.

Today, epiphytes comprise about 30 percent of the more than 9,000 living fern species. But this isn’t the only plant group that includes epiphytes. This fall, as a post-doctoral fellow at the National Evolutionary Synthesis Center (NESCent), Schuettpelz will begin to look for parallel patterns of diversification in epiphytic flowering plants like bromeliads and orchids.

Pryer and Schuettpelz received support from the National Science Foundation.

Flowering plant evolution: here.

Great white shark, megalodon, and evolution

From ScienceDaily:

Preserved Shark Fossil Adds Evidence To Great White‘s Origins

(Mar. 13, 2009) — A new University of Florida study could help resolve a long-standing debate in shark paleontology: From which line of species did the modern great white shark evolve?

For the last 150 years, some paleontologists have concluded the great white shark, Carcharodon carcharias, is a smaller relative of the line that produced Carcharodon megalodon, the largest carnivorous fish known. Other paleontologists disagree, arguing the great white shark evolved instead from the broad-toothed mako shark. The second group contends megalodon, which grew to a length of 60 feet, should have its genus name switched to Carcharocles to reflect its different ancestry.

The study in the March 12 issue of the Journal of Vertebrate Paleontology falls squarely into the mako camp. It concludes megalodon and modern white sharks are much more distantly related than paleontologists initially believed.

“I think that this specimen will clarify things,” said lead author Dana Ehret, a vertebrate paleontology graduate student at the Florida Museum of Natural History located on the UF campus. “When we only have isolated teeth to describe, it’s very hard to come to a definitive conclusion.”

The study is based on a remarkably well preserved 4- to 5-million-year-old fossil from Peru of an early white shark species: a complete jaw with 222 teeth intact and 45 vertebrae. Most ancient shark species are known only from isolated teeth. Based on tooth size and analysis of growth rings within the vertebrae, the shark was about 20 years old and 17 to 18 feet long, a size in the range of modern white sharks.

Having the teeth in place allows researchers to see important distinguishing characteristics that help determine a fossil’s genus and species, such as whether a tooth curves toward the outside of the jaw or its midline, Ehret said. He believes the fossil belongs to a white shark species closely related to Isurus hastalis, a broad-toothed mako shark that probably grew to 27 feet long and lived 9 million to 10 million years ago.

An olive-grove farmer trained in fossil collection discovered it near his home in the desert of southern Peru in 1988. It now belongs to a private collection and was only recently pledged to the Florida Museum of Natural History. …

The specimen came from an area known as the Pisco Formation, famous for its rich fossil beds dating from the late Miocene to Pleistocene, about 1 million to 9 million years ago. The region was once a sheltered, shallow marine environment ideal for preserving skeletons. The formation has produced articulated broad-toothed mako shark skeletons as well as fossils of whales, aquatic sloths and sea turtles.

The study strengthens the evolutionary link between the extinct mako and the modern white shark, said vertebrate paleontologist Kenshu Shimada, an associate professor at DePaul University in Chicago. Shimada said paleontologists now need fossil skeletons from megalodon and a shark from the extinct Otodontidae family such as Otodus, a large prehistoric mackerel shark that lived about 40 million to 60 million years ago.

“If we can demonstrate the strong link between Carcharocles and Otodus from such skeletal remains,” Shimada said, “we may be able to settle the evolutionary and taxonomic debates.”

Megalodon was first classified in the same genus as the modern white shark in the 1840s based on the similarity of tooth shape and serrations specialized for eating marine mammals. Mako sharks have no serrations because they feed primarily on fish.

Ehret says the shark fossil’s coarse serrations are evidence of a transition between broad-toothed mako sharks and modern white sharks.

“Here we have a shark that’s gaining serrations,” he said. “It’s becoming a white shark, but it’s not quite there yet.”

The transition from megatooth sharks like megalodon to modern white sharks would require changes in body size and tooth serrations, thickness and enamel, Ehret said. By contrast, the transition from the broad-toothed mako shark to modern white sharks would require only the presence of serrations and a shift in the slant of a key tooth position.

Economic Recession Means Fewer Shark Attacks: here.

Vast Bed of Ancient Bones and Shark Teeth Explained: here.

33,000 sharks, 2000 dolphins & 2000 turtles killed to boost beach tourism in South Africa: here.

Great whites ‘plan’ seal attacks: here.

Largest prehistoric Megalodon shark jaw ever assembled up for auction: here.

Snake fang evolution discoveries

This National Geographic video is called Cobra vs. Rat Snake.

From Science News:

How the snake got its fangs

By Amy Maxmen

July 30th, 2008
Web edition

“How’d you get those newfangled teeth?” hissed the petite garter snake to the venomous cobra. “Same way that you got yours,” cobra replied. All fangs — no matter their size, shape or position — descend from a single evolutionary event, new evidence from snake embryos suggests. …

The new study, led by Freek Vonk of Leiden University in The Netherlands, reveals that snakes didn’t reinvent the wheel with each new version of their venom-delivery systems. The report appears in the July 31 Nature.

Rapid venom evolution in pit vipers may be defensive: here.

Garter snake photo: here.

Eastern garter snake: here.