Fossil embryos turn out to be jellyfish


Pseudooides. Credit: University of Bristol

From the University of Bristol in England:

Fossil orphans reunited with their parents after half a billion years

December 13, 2017

Everyone wants to be with their family over the holidays, but spare a thought for a group of orphan fossils that have been separated from their parents since the dawn of animal evolution, over half a billion years ago.

For decades, paleontologists have puzzled over the microscopic fossils of Pseudooides, which are smaller than sand grains.

The resemblance of the fossils to animal embryos inspired their name, which means ‘false egg’.

The fossils preserve stages of embryonic development frozen in time by miraculous processes of fossilisation, which turned their squishy cells into stone.

Pseudooides fossils have a segmented middle like the embryos of segmented animals, such as insects, inspiring grand theories on how complex segmented animals may have evolved.

A team of paleontologists from the University of Bristol‘s School of Earth Sciences and Peking University have now peered inside the Pseudooides embryos using X-rays and found features that link them to the adult stages of another fossil group.

It turns out that these adult stages were right under the scientists’ noses all along: they have been found long ago in the same rocks as Pseudooides.

Surprisingly, these long-lost family members are not complex segmented animals at all, but ancestors of modern jellyfish.

Dr Kelly Vargas from the University of Bristol said: “It seems that, in trying to classify these fossils, we’ve previously been barking up the wrong branch of the animals family tree.”

Professor Philip Donoghue, also from the University of Bristol, co-led the research with Professor Xiping Dong of Peking University.

Professor Donoghue added “We couldn’t have reunited these ancient family members without the amazing technology which allowed us to see inside the fossilized bodies of the embryos and adults.”

The team used the Swiss Light Source, a gigantic particle accelerator near Zurich, Switzerland, to supply the X-rays used to image the inside of the fossils.

This showed that the details of segmentation in the Pseudooides embryos to be nothing more than the folded edge of an opening, which developed into the rim of the cone-shaped skeleton that once housed the anemone-like stage in the life cycle of the ancient jellyfish.

Luis Porras, who helped make the discovery while still a student at the University of Bristol, said: “Pseudooides fossils may not tell us about how complex animals evolved, but they provide insights into the how embryology of animals itself has evolved.

“The embryos of living jellyfish usually develop into bizarre alien-like larvae which metamorphose into anemone-like adults before the final jellyfish (or ‘medusa‘) phase.

“Pseudooides did things differently and more efficiently, developing directly from embryo to adult. Perhaps living jellyfish are a poor guide to ancestral animals.”

Professor Donoghue added: “It is amazing that these organisms were fossilised at all.

“Jellyfish are made up of little more than goo and yet they’ve been turned to stone before they had any chance to rot: a mechanism which some scientists refer to as the ‘Medusa effect’, named after the gorgon of Greek mythology who turned into stone anyone that laid eyes upon her.”

The Bristol team are still looking for fossil remains of the rest of Pseudooides life cycle, including the ‘medusa’ jellyfish stage itself. However, jellyfish fossils are few and far between, perhaps ironically because the ‘Medusa effect’ doesn’t seem to work on them.

In the interim, the embryos of Pseudooides have been reunited with their adult counterparts, just in time for Christmas.

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North American Cooper’s hawks, new research


This video from the USA is called Cooper’s Hawk Bathing And Flying Away.

From the American Ornithological Society Publications Office in the USA:

Urban Cooper’s hawks outcompete their rural neighbors

December 13, 2017

Depending on whether a species flourishes in a city environment, urban wildlife populations can be “sources” or “sinks,” either reproducing so quickly that individuals leave to colonize the surrounding area or needing constant immigration from outside to stay viable. A new study from The Condor: Ornithological Applications examines the population dynamics of Cooper’s Hawks in urban Albuquerque, New Mexico, and finds that city-born birds aren’t just thriving — they’re actually forcing their rural neighbors out of their nest sites.

New Mexico State University’s Brian Millsap collected data on Cooper’s Hawks living in a 72 square kilometer area of northeast Albuquerque from 2011 to 2015, monitoring each year’s nests and tracking newly fledged females with radio transmitters. He found that 30 times more hawks emigrated out of the urban area than immigrated into it, suggesting it was a source population for the surrounding region. However, the details didn’t fit neatly with the traditional source-sink model. While the surrounding exurban hawk populations were breeding and surviving well enough to sustain themselves without immigration, females moving out of the urban area were able to beat them to their nesting sites — unlike their exurban neighbors, they didn’t migrate south for the winter.

White-winged Doves, which first became established in the area in the 1980s, provide an abundant food source for city-dwelling hawks. “Individuals living in urban Albuquerque actually have a fitness advantage over their neighbors living in natural habitats. This advantage comes from the higher prey populations in urban areas, which allow urban female Cooper’s Hawks to spend the winter near their eventual breeding sites, as opposed to rural females that migrate south in winter,” explains Millsap. “The urban female hawks begin searching out and claiming nesting territories before the rural hawks return in spring and thus obtain nesting sites without direct competition from migrants. Because of this advantage, the urban Albuquerque Cooper’s Hawk population not only supports itself but also serves as a substantial source of immigrant females for surrounding native habitats.”

Changes in migratory behavior that lead to segregation between different groups can have profound effects on populations, altering how they interact both with each other and with other species in a community. According to the Peregrine Fund’s Chris McClure, an expert on raptor ecology, “This study is a great example of how solid field work and sophisticated modeling can yield new insights in basic and applied ecology.”

Crow harasses feeding buzzard


This 12 December 2017 video shows a carrion crow harassing a feeding buzzard at the Brouwersdam causeway in the Netherlands.

The buzzard kept eating. After it left, three carrion crows quarreled about the leftovers.

Jannie Timmer made this video.

Feeding buzzards being harassed photos are here.

Great tits, blue tits in the snow


This 12 December 2017 video shows great tits and blue tits feeding in the snow.

Simone Kuijt made this video behind the window of her home in the Netherlands.

Bulls fighting in the snow, video


This 12 December 2017 video is about two highland cattle bulls fighting in the snow in the Deelerwoud nature reserve in the Veluwe region in the Netherlands.

Ineke Davidse made this video.

Human-sized fossil penguin discovery


This video from the USA says about itself:

Ancient penguin was as big as a (human) Pittsburgh Penguin

12 December 2017

NEW YORK — Fossils from New Zealand have revealed a giant penguin that was as big as a grown man, roughly the size of the captain of the Pittsburgh Penguins. The creature was slightly shorter in length and about 20 pounds heavier than the official stats for hockey star Sidney Crosby.

It measured nearly 5 feet, 10 inches long when swimming and weighed in at 223 pounds. If the penguin and the Penguin faced off on the ice, however, things would look different. When standing, the ancient bird was maybe only 5-foot-3.

The newly found bird is about 7 inches longer than any other ancient penguin that has left a substantial portion of a skeleton, said Gerald Mayr of the Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany. A potentially bigger rival is known only from a fragment of leg bone, making a size estimate difficult.

The biggest penguin today, the emperor in Antarctica, stands less than 4 feet tall. Mayr and others describe the giant creature in a paper released Tuesday by the journal Nature Communications.

They named it Kumimanu biceae, which refers to Maori words for a large mythological monster and a bird, and the mother of one of the study’s authors. The fossils are 56 million to 60 million years old. That’s nearly as old as the very earliest known penguin fossils, which were much smaller, said Daniel Ksepka, curator at the Bruce Museum of Greenwich, Connecticut.

He has studied New Zealand fossil penguins but didn’t participate in the new study. The new discovery shows penguins “got big very rapidly” after the mass extinction of 66 million years ago that’s best known for killing off the dinosaurs, he wrote in an email.

That event played a big role in penguin history. Beforehand, a non-flying seabird would be threatened by big marine reptile predators, which also would compete with the birds for food. But once the extinction wiped out those reptiles, the ability to fly was not so crucial, opening the door for penguins to appear.

Birds often evolve toward larger sizes after they lose the ability to fly, Mayr said. In fact, the new paper concludes that big size appeared more than once within the penguin family tree. What happened to the giants? Mayr said researchers believe they died out when large marine mammals like toothed whales and seals showed up and provided competition for safe breeding places and food. The newcomers may also have hunted the big penguins, he said.

From LiveScience:

Giant Penguin: This Ancient Bird Was As Tall As a Refrigerator

By Laura Geggel, Senior Writer

December 12, 2017 03:21pm ET

The fossils of a refrigerator-size penguin were so gargantuan that the scientists who discovered them initially thought they belonged to a giant turtle. The ancient behemoth is now considered the second-largest penguin on record.

The newfound penguin species would have stood nearly 6 feet tall (1.8 meters) and weighed about 220 lbs. (100 kilograms) during its heyday tens of millions of years ago.

The bird’s gigantism indicates that “a very large size seems to have developed early on in penguin evolution, soon after these birds lost their flight capabilities,” said study co-lead researcher Gerald Mayr, a curator of ornithology at the Senckenberg Research Institute, in Germany. [In Photos: The Amazing Penguins of Antarctica]

At first, the researchers thought the penguin fossils belonged to a turtle, said study co-lead researcher Alan Tennyson, a vertebrate curator at the Museum of New Zealand (Te Papa Tongarewa), who discovered the fossil with paleontologist Paul Scofield on a beach in New Zealand’s Otago province in 2004.

But shortly after a fossil technician began preparing the specimen in 2015, he found a part of the shoulder blade, known as the coracoid, which revealed that the fossils came from a penguin, Tennyson told Live Science.

Further analysis dated the penguin to between 55 million and 59 million years ago, meaning that it lived a mere 7 million to 11 million years after an asteroid slammed into Earth and killed the nonavian dinosaurs, Mayr said.

The researchers named the late-Paleocene penguin Kumimanu biceae. Its genus name, Kumimanu, was inspired by the Maori indigenous culture of New Zealand. In the Maori culture, “kumi” is a mythological monster, and “manu” is the Maori word for “bird.” The species name, biceae, honors Tennyson’s mother, Beatrice “Bice” A. Tennyson, who encouraged him to pursue his interest in natural history.

K. biceae didn’t look much like modern penguins. Although researchers could not find its skull, they “know from similarly aged fossils that the earliest penguins had much longer beaks, which they probably used to spear fishes, than their modern relatives [do],” Mayr told Live Science. Like its modern cousins, however, K. biceae would have already developed typical penguin feathers, waddled with an upright stance and sported flipper-like wings that helped it swim, he added.

Researchers have discovered other ancient penguin fossils in New Zealand, including those of Waimanu manneringi, which lived about 61 million years ago. However, the largest penguin on record is Palaeeudyptes klekowskii, which lived about 37 million years ago in Antarctica. P. klekowskii stood about 6.5 feet (2 m) tall and weighed a whopping 250 lbs. (115 kg), according to a 2014 study in the journal Comptes Rendus Palevol (Palevol Reports).

Given that the Antarctic penguin was larger than K. biceae, it’s likely that “giant size evolved more than once in penguin evolution”, Mayr said.

K. biceae is a “cool fossil,” said Daniel Ksepka, a curator at the Bruce Museum in Greenwich, Connecticut, who was not involved in the research. “It’s very old; it’s almost as old as the oldest known penguins anywhere”, Ksepka told Live Science. “That shows that [penguins] got big really quickly. And it all seems to have happened in New Zealand.” [Photos of Flightless Birds: All 18 Penguin Species]

But why was New Zealand a penguin paradise? The archipelago was surrounded by fish for penguins to eat, and it originally had no native mammals (although today it’s home to many sheep, weasels and domestic pets), meaning that there were no predators to bother the penguins when they came ashore to molt their feathers and lay eggs, Ksepka said.

The study was published online today (Dec. 12) in the journal Nature Communications.