Prehistoric harvestman had extra eyes


This video says about itself:

10 April 2014

A 305-million-year-old harvestman fossil, ancestor of modern day arachnids, is more closely relates to the scorpions than spiders. Scientists discovered unusual features: it has 2 sets of eyes on the center and lateral sides of the body.

From Discovery News:

Ancient Daddy Longlegs Had Extra Eyes

APRIL 12, 2014 12:30 PM ET // BY PAUL HELTZEL

A 304-million-year-old fossil discovered in Eastern France shows primitive living harvestmen — more commonly called daddy longlegs — had one more pair of eyes than they do today.

The ancient harvestmen had a pair of eyes along the middle of the body — like their modern counterparts — but they also had a pair of eyes on the side of the body. The findings were reported by researchers from the American Museum of Natural History and the University of Manchester, in the journal Current Biology.

Photos: Look If You Dare: Ancient Spider Family Album

Scientists studied the fossil using high-resolution X-ray imaging at the Natural History Museum, London.

“Our X-ray techniques have allowed us to reveal this fossil in more detail than we would have dreamed possible two decades ago,” said Russell Garwood, a research fellow at the University of Manchester and a lead author on the study, in a release.

Though Harvestmen have eight legs and are categorized as arachnids, they’re not spiders. They’re more closely related to scorpions.

The scientists also examined the expression of an eye-stalk growing gene in harvestmen embryos. The embryos briefly express the gene for the second pair of eyes. But by the time they hatch, the daddy long legs’ second pair of eyes are long gone.

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Cambrian prehistoric predator evolution, new research


This video says about itself:

26 March 2014

T[amisiocaris]. borealis, an ancient predator, probably used its spiny appendages to sweep through the water for prey and then bring it into its mouth, as these animations show. Credit: Martin Stein. Read more here.

From Wildlife Extra:

Large ocean predators evolved into gentle giants 520 million years ago

April 2014: Large marine creatures that roamed the Earth’s oceans more than 520 million years ago have been found to filter food from the water in a similar way to today’s blue whales and evolved into a gentle sea giant from a large marine predator that feasted on large prey, say scientists.

Newly discovered fossils from North Greenland showed that these ancient giant marine animals used bizarre facial appendages to trawl for nekton and plankton from the seas.

The North Greenland fossil, called Tamisiocaris, was a member of the iconic anomalocarids group of early marine animals which roamed the Cambrian and later Ordovician oceans. They swam using a set of flaps down either side of the body and probably captured large prey with specialised grasping appendages in the front of the mouth.

The team demonstrates that the Tamisiocaris had evolved into a suspension feeder by modifying its grasping appendages into a filtering apparatus that could be swept like a net through the water trapping small crustaceans and other organisms as tiny as half a millimetre in size.

The research, funded by the Agouron Institute, Carlsberg Foundation and Geocenter Denmark, was led by the University of Bristol and also included researchers at Durham University, the University of Bath and the University of Copenhagen.

As well as shedding light on the evolution of the Tamisiocaris, the researchers said their discovery also showed how productive the Cambrian period was and how vastly different species of anomalocarids evolved at that time. It also provides further clues into the ecosystems that existed hundreds of millions of years ago, they said.

Study lead author Dr Jakob Vinther, a lecturer in macroevolution at the University of Bristol, said: “The fact that large, free-swimming suspension feeders roamed the oceans tells us a lot about the ecosystem.

“Feeding on the smallest particles by filtering them out of the water while actively swimming around requires a lot of energy – and therefore lots of food.”

In order to fully understand how an anomalocarid could have fed, Dr Martin Stein from the University of Copenhagen, Denmark, created a 3D computer animation of the feeding appendage to explore the range of movements it could have made.

Dr Stein said: “Tamisiocaris would have been a sweep net feeder, collecting particles in the fine mesh formed when it curled its appendage up against its mouth.

“This is a rare instance when you can actually say something concrete about the feeding ecology of these types of ancient creatures with some confidence.”

The research about this was published here.

April 2014: An international team of researchers from the US, China and the UK have discovered the earliest known cardiovascular system in fossilised remains of an extinct marine shrimp that lived over 520 million years ago. The finding sheds new light on the evolution of the body in the animal kingdom and shows that even the earliest creatures had internal systems that strongly resemble those found in their modern descendants: here.

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New Mexico dinosaurs, new study


This video is called Theropod cladogram.

From PLOS ONE:

Small Theropod Teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and Their Implications for Understanding Latest Cretaceous Dinosaur Evolution

Thomas E. Williamson, Stephen L. Brusatte

Published: April 07, 2014

Abstract

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs.

Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns.

We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian – Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas.

The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately co-eval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species.

A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern [is] seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction.

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Some prehistoric sloths were ocean swimmers


This video is called Giant Ground Sloth – Museum of Life – BBC Two.

From National Geographic:

Some Ancient Sloths Ventured Into the Ocean, Study Says

Posted by Jane J. Lee in Weird & Wild on March 11, 2014

Modern-day sloths are tree dwellers, only occasionally venturing down to the ground. But about five to eight million years ago, five sloth species ventured into the sea.

Now, new research suggests that these ancient animals went much further into the water than we ever knew. Instead of just living near the ocean and making brief forays in, as scientists had previously thought, it appears that ancient aquatic sloths swam out and dove toward the bottom for food. The study confirms habits scientists had speculated about for years.

In studying the aquatic sloth fossils, a team of scientists found that cavities present in the bones of terrestrial animals were absent in the sloth specimens. They were instead filled with solid bone, which aided in diving.

“Think about a scuba diver who has a weight belt,” says Eli Amson, a paleontologist at the National Museum of Natural History in Paris and lead study author. “It allows them to sink.”

The bones of terrestrial mammals, by contrast—including our own—are filled with small cavities.

Dense bone is one of the key adaptations seen in mammals such as manatees and dugongs that returned to the sea, where life began. Dense bones would have been especially important in helping aquatic sloths dive because they had big bellies, like modern sloths do, which would have acted like flotation devices, says Greg McDonald, a senior curator of natural history for the U.S. National Park Service.

The earliest aquatic sloths probably came down to the beaches to munch on sea grasses exposed to the air during low tides, McDonald says. The animals may have waded into shallow water to graze on vegetation.

“Over time, [the sloths] become better adapted to an aquatic habitat where they go out and swim,” McDonald says, “and dive down in order to feed more often and not just with the tides.”

Beach Bums?

Other adaptations to a watery lifestyle can be seen in the ancient sloths’ limbs and tails. On average, these animals were 6.5 to 8 feet (2 to 2.5 meters) long, with about 3 feet (a meter) of that length being all tail, says Amson.

“The tail is actually reminiscent of a platypus tail or a beaver tail,” he says. But the sloths probably weren’t using their paddle-like tail for locomotion underwater. It was probably working to keep the animals stable as they dove, Amson explains.

Modifications to bones in their upper and lower legs also point to a shift to a more aquatic lifestyle, McDonald says.

Sloths didn’t get to a point where they were as aquatic as modern seals or sea lions, he adds. Aquatic sloths probably did come back to land to bask in the sun and warm up between meals.

And what a sight that would have been, to see six-foot (two-meter) sloths lazing about a beach. “Even by sloth standards, it’s a weird animal,” McDonald says. (Learn more about aquatic sloths.)

The new study was published this week in the Proceedings of the Royal Society B.

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Asian fossil birds, new research


This video says about itself:

Two of Papua New Guinea‘s many birds of paradise – the Magificent and the King – put on an show of dancing and hanging upside down in spectacular courtship display.

By Hanneke J.M. Meijer:

The avian fossil record in Insular Southeast Asia and its implications for avian biogeography and palaeoecology

Abstract

Excavations and studies of existing collections during the last decades have significantly increased the abundance as well as the diversity of the avian fossil record for Insular Southeast Asia. The avian fossil record covers the Eocene through the Holocene, with the majority of bird fossils Pleistocene in age. Fossil bird skeletal remains represent at least 63 species in 54 genera and 27 families, and two ichnospecies are represented by fossil footprints. Birds of prey, owls and swiftlets are common elements.

Extinctions seem to have been few, suggesting continuity of avian lineages since at least the Late Pleistocene, although some shifts in species ranges have occurred in response to climatic change. Similarities between the Late Pleistocene avifaunas of Flores and Java suggest a dispersal route across southern Sundaland. Late Pleistocene assemblages of Niah Cave (Borneo) and Liang Bua (Flores) support the rainforest refugium hypothesis in Southeast Asia as they indicate the persistence of forest cover, at least locally, throughout the Late Pleistocene and Holocene.

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Sponges made human evolution possible, new research


This video is called Sponge Feeding.

From daily Haaretz in Israel:

The precursor to life on earth? The humble sponge, new research says

New paper says sea sponges may have led to more oxygenated water in the deep ocean, leading to evolution of more complex forms of life on earth – including humans.

Mar. 10, 2014 | 12:15 PM

Sea sponges may have been the precursor to all life on earth, including human life, according to new research.

A new paper published in the Nature Geoscience journal says that sea sponges may have added oxygen to the deep ocean, helping forge an environment where more complex life forms could evolve, Discovery News reported Monday.

Earlier this year, research found that the earliest sponges could have survived in waters with very little oxygen. The research presented in this latest paper builds on this.

“There had been enough oxygen in ocean surface waters for over 1.5 billion years before the first animals evolved, but the dark depths of the ocean remained devoid of oxygen,” said a press release from Tim Lenton of the University of Exeter, according to Discovery News. “We argue that the evolution of the first animals could have played a key role in the widespread oxygenation of the deep oceans. This in turn may have facilitated the evolution of more complex, mobile animals,” the press release said.

According to DNA analysis, sea sponges first emerged at least 700 million years ago – a time when the oceans contained little oxygen. Oxygen levels in the oceans rose between 700 and 600 million years ago, and animal fossils have been found dating to 650 million years ago.

The above is some of the evidence that supports the theory. The way that sponges feed is further evidence, Discovery News said. As they feed, water circulates through sponges, carrying nutrients, and also particles of organic matter. All those years ago, these particles would have included dead microbial matter that eats up oxygen as it rots. Removing these rotting particles from the ocean would have led to increased oxygen in the water, according to researchers.

With more oxygen, more complex life forms would have been able to emerge, including animals that prey on each other, and eat each other, according to Discovery News. This would have paved the way for today’s food webs and the marine ecosystem.

The theory that earth creatures, including humans, first evolved from underwater ones is widely accepted, Discovery News noted, adding that scientists believe sponges may have been an “Animal Eve” that led to the evolution of all animals today.

The research also solves the riddle of whether oxygenated waters predated the humble sponge, or the other way around. “The effects we predict suggest that the first animals, far from being a passive response to rising atmospheric oxygen, were the active agents that oxygenated the ocean around 600 million years ago,” the researchers said. “They created a world in which more complex animals could evolve, including our very distant ancestors.”

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Ice Age fossils discovery in Los Angeles


This video from the USA says about itself:

20 Sep 2010

A utility company preparing to build a new substation southeast of Los Angeles has stumbled on a trove of fossils dating back 1.4 million years. The cache contains nearly 1,500 fossils, including an ancestor of the saber-toothed tiger.

From USA Today:

Ice Age fossils discovered in L.A. subway construction

10:07 a.m. EST March 7, 2014

An exploratory dig for Los Angeles’ subway extension project has uncovered Ice Age fossils.

The discoveries so far have included geoducks (large clams), sand dollars and digger pine tree cones and seeds, and a rock that “appears to have a sea lion skull within it that is perhaps two million years or more old,” according to the Metro Rail’s blog.

The expansion of L.A.’s purple line is near the La Brea Tar Pits, where many fossils have been found.

The exploratory shaft for the subway route is now 65 feet deep, according to Metro.

“We expect that we’re going to find large deposits of late Ice Age vertebrate remains,” said Aisling Farrell, collections manager at Page Museum at the La Brea Tar Pits, in an interview with KABC-TV in Los Angeles.

Metro is working with the museum to identify and preserve the fossils, according to Metro.

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Biggest European carnivorous dinosaur discovery in Portugal


Torvosaurus tanneri in Madrid museum

From PLOS ONE:

Torvosaurus gurneyi n. sp., the Largest Terrestrial Predator from Europe, and a Proposed Terminology of the Maxilla Anatomy in Nonavian Theropods

Christophe Hendrickx, Octávio Mateus

Published: March 05, 2014

Abstract

The Lourinhã Formation (Kimmeridgian-Tithonian) of Central West Portugal is well known for its diversified dinosaur fauna similar to that of the Morrison Formation of North America; both areas share dinosaur taxa including the top predator Torvosaurus, reported in Portugal.

The material assigned to the Portuguese T. tanneri, consisting of a right maxilla and an incomplete caudal centrum, was briefly described in the literature and a thorough description of these bones is here given for the first time. A comparison with material referred to Torvosaurus tanneri allows us to highlight some important differences justifying the creation of a distinct Eastern species.

Torvosaurus gurneyi n. sp. displays two autapomorphies among Megalosauroidea, a maxilla possessing fewer than eleven teeth and an interdental wall nearly coincidental with the lateral wall of the maxillary body. In addition, it differs from T. tanneri by a reduced number of maxillary teeth, the absence of interdental plates terminating ventrally by broad V-shaped points and falling short relative to the lateral maxillary wall, and the absence of a protuberant ridge on the anterior part of the medial shelf, posterior to the anteromedial process.

T. gurneyi is the largest theropod from the Lourinhã Formation of Portugal and the largest land predator discovered in Europe hitherto. This taxon supports the mechanism of vicariance that occurred in the Iberian Meseta during the Late Jurassic when the proto-Atlantic was already well formed. A fragment of maxilla from the Lourinhã Formation referred to Torvosaurus sp. is ascribed to this new species, and several other bones, including a femur, a tibia and embryonic material all from the Kimmeridgian-Tithonian of Portugal, are tentatively assigned to T. gurneyi. A standard terminology and notation of the theropod maxilla is also proposed and a record of the Torvosaurus material from Portugal is given.

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Did Chilean prehistoric whales die from algae?


This video says about itself:

Smithsonian 3D Digi Landscape – Chilean Fossil Whales – Time Lapse

26 November 2011

9 exposure HDR time lapse shot overnight. Newly discovered fossil whales in foreground with the Pan-american Highway leading towards the port of Caldera, Chile.

From Wildlife Extra:

Ancient marine graveyard mystery solved

February 2014: The 40 marine mammals that washed up on the Chilean coast millions of years ago died at sea probably from being poisoned by toxic algal blooms say scientists.

The marine graveyard was discovered in 2011 when builders working to extend the Pan-American Highway discovered a 250 metre wide quarry site filled with the skeletons of more than 40 marine mammals including 31 large baleen whales, seals, a walrus-like toothed whale, an aquatic sloth and an extinct species of sperm whale, suggesting that they died from the same cause.

The wide array of animals buried at the site over four levels indicated that the cause of death didn’t differentiate between the young and old or between species, and occurred repeatedly over thousands of years. This suggests that harmful algae blooms, which cause organ failure, could be the most common cause of mass strandings.

Other causes, like tsunamis, were ruled out by the team of Chilean and Smithsonian paleontologists because they would have produced a range of skeletons including much smaller species, rather than the primarily large mammals found at Cerro Ballena. A mass stranding while alive was ruled out as a cause of death due to the way all the marine mammals were were found at right angles to the direction that the current would have flowed.

Humans have been using echolocation in the form of sonar since the early part of the 20th century, but whales have made use of the ability to use sound to pinpoint locations for tens of millions of years. As evidenced in the fossils – which belong to a new species of ancient whale named Cotylocara macei – cetaceans have been using echolocation for at least 30 million years: here.

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Prehistoric apes discovery in Kenya


This video says about itself:

1 Oct 2012

On Rusinga Island in Kenya‘s Lake Victoria, paleontologist Will Harcourt-Smith is leading an effort to recreate the environments inhabited by primitive primates—apes of the genus Proconsul. Studying the adaptive changes of our ancient ancestors helps scientists trace the origins of adaptability in modern humans.

Science Bulletins is a production of the National Center for Science Literacy, Education, and Technology (NCSLET), part of the Department of Education at the American Museum of Natural History.

From Science, Space & Robots:

Fossil Forest Discovery Sheds Light on Environment Inhabited by Early Apes

A fossil forest discovery by researchers from Baylor University and an international team of scientists has shed light on the environment inhabited by early apes on Rusinga Island, Kenya. Researchers found fossils of tree stumps, calcified roots and fossil leaves. Researchers say the fossil find indicates that Proconsul and its primate relative, Dendropithecus, lived in a dense, closed canopy tropical seasonal forest about 18 to 20 million years ago. The research was published here in Nature Communications.

Daniel Peppe, Ph.D., assistant professor of geology in Baylor’s College of Arts and Sciences and co-author of the study, says in a Baylor release, “Our research findings provide direct evidence and confirm where the early ape lived about 18 to 20 million years ago. We now know that Proconsul lived in a closed-canopy, tropical seasonal forest set in a warm and relatively wet local climate.”

Fossils of a single Proconsul were also found among the geological fossil forest deposits.

Lauren Michel, lead author of the study and a doctoral student in the geology department at Baylor, says, “The varying diameters of the tree stumps coupled with their density within the fossil soil, implies that the forest would have been comprised of trees with interlocking or overlapping branches, thus creating a canopy.”

Posted on February 27, 2014

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