Giant Paleocene penguin discovery in New Zealand


Reconstruction of newly discovered Crossvallia waiparensis penguin, next to human to show size, picture by Canterbury Museum

From the Canterbury Museum in New Zealand:

Monster penguin find in Waipara, New Zealand

August 14, 2019

A new species of giant penguin — about 1.6 metres tall — has been identified from fossils found in Waipara, North Canterbury.

The discovery of Crossvallia waiparensis, a monster penguin from the Paleocene Epoch (between 66 and 56 million years ago), adds to the list of gigantic, but extinct, New Zealand fauna. These include the world’s largest parrot, a giant eagle, giant burrowing bat, the moa and other giant penguins.

C. waiparensis is one of the world’s oldest known penguin species and also one of the largest — taller even than today’s 1.2 metre Emperor Penguin — and weighing up to 70 to 80 kg.

A team comprising Canterbury Museum curators Dr Paul Scofield and Dr Vanesa De Pietri, and Dr Gerald Mayr of Senckenberg Natural History Museum in Frankfurt, Germany, analysed the bones and concluded they belonged to a previously unknown penguin species.

In a paper published this week in Alcheringa: An Australasian Journal of Palaeontology, the team concluded that the closest known relative of C. waiparensis is a fellow Paleocene species Crossvallia unienwillia, which was identified from a fossilised partial skeleton found in the Cross Valley in Antarctica in 2000.

Canterbury Museum Senior Curator Natural History Dr Paul Scofield says finding closely related birds in New Zealand and Antarctica shows our close connection to the icy continent.

“When the Crossvallia species were alive, New Zealand and Antarctica were very different from today — Antarctica was covered in forest and both had much warmer climates,” he says.

The leg bones of both Crossvallia penguins suggest their feet played a greater role in swimming than those of modern penguins, or that they hadn’t yet adapted to standing upright like modern penguins.

C. waiparensis is the fifth ancient penguin species described from fossils uncovered at the Waipara Greensand site.

Dr Gerald Mayr says the Waipara Greensand is arguably the world’s most significant site for penguin fossils from the Paleocene Epoch. “The fossils discovered there have made our understanding of penguin evolution a whole lot clearer,” he says. “There’s more to come, too — more fossils which we think represent new species are still awaiting description.”

Dr Vanesa De Pietri, Canterbury Museum Research Curator Natural History, says discovering a second giant penguin from the Paleocene Epoch is further evidence that early penguins were huge. “It further reinforces our theory that penguins attained a giant size very early in their evolution,” she says.

The fossils of several giant species, including C. waiparensis, will be displayed in a new exhibition about prehistoric New Zealand at Canterbury Museum later this year.

This research was partly supported by the Royal Society of New Zealand’s Marsden Fund.

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Endangered South African penguins, video


This 29 July 2019 video says about itself:

Endangered Penguins of South Africa – 360 | National Geographic

The populations of African penguins, a species of penguins found along the coasts of South Africa and Namibia, are declining largely due to the depletion of fish stocks in the sea, and habitat encroachment. See them in their natural habitat and how the injured or abandoned of these seabirds are being rehabilitated.

Sponges help studying penguin, seal, fish DNA


This 2016 video says about itself:

Sponges: Oldest Creatures in the Sea? – Full Episode

Until recently there was a scientific consensus that sponges were the first animals to branch off the “Animal Tree of Life”, a kind of family tree for all living and extinct animals on earth. But recent DNA research has cast doubt on that theory, with some scientists suggesting that ctenophores, also known as comb jellies, are an older lineage.

From ScienceDaily:

Sponges collect penguin, seal, and fish DNA from the water they filter

June 3, 2019

Just like humans leave DNA in the places we inhabit, water-dwelling animals leave DNA behind in the water column. In a paper published June 3 in the journal Current Biology, scientists report that sponges, which can filter 10,000 liters of water daily, catch DNA in their tissues as they filter-feed. This proof-of-concept study identified fish, seal, and penguin DNA in sponges from the Antarctic and Mediterranean, demonstrating that sponges can be used to monitor biodiversity.

“Sponges are ideal sampling units because you find them everywhere and in every aquatic habitat, including freshwater,” says Stefano Mariani, a marine ecologist and population geneticist at the University of Salford. “Also, they’re not very selective filter-feeders, they don’t run away, and they don’t get hurt by sampling — you can just grab a piece, and they will regenerate nicely.”

Additionally, the authors found that the presence of sponge DNA did not interfere with their ability to identify the DNA of other species caught within its tissue. Instead, they found that by using a particular DNA primer, which is a short sequence of nucleic acid that probes the DNA of specific organisms, they could selectively amplify vertebrate DNA while avoiding amplifying the sponge’s DNA itself.

Using this process in tandem with metabarcoding, which sorts the jumble of DNA from the tissue sample into distinguishable, species-specific piles, Mariani and his team were able to identify 31 taxa. Mostly, the species identified were fish, but one sponge sample from Antarctica included DNA from Weddell seals and chinstrap penguins. The sample was later identified to be located offshore of a penguin breeding colony. “This was a really exciting find and also makes a lot of sense,” says Mariani, “because the penguins would be in and out of the water a lot, eating, swimming, and pooing.”

Currently, machines with large water-sampling capabilities are being developed to allow scientists to sample DNA from water, but the authors think using a natural sampler could be just as effective. Because the DNA found in water is extremely diluted, it needs to undergo extensive filtering — but with filtering, Mariani warns, comes the danger of DNA contamination. Further, preserving water samples risks degrading the DNA. Sponge tissue, however, has already filtered out the water, greatly reducing both the processing time as well as the risk of contamination.

Further, bringing machines into some regions might not be feasible and may be too disruptive to fragile ecosystems. “If you want to study an endangered species of sawfish or a manatee in a mangrove forest in Mozambique, you can’t go there with massive robots. You have to use a very low-tech approach,” Mariani says.

Moving forward, the authors would like to investigate the ability of other animals to act as DNA samplers, particularly in open waters where sponges are either rare or unreachable by humans for sampling. Mariani suggests that other organisms such as jelly fish or salps, which also sieve water but float through the water column, may be more accessible in the open ocean.

Ultimately, the authors’ goal is to improve how environmental DNA is collected in order to better monitor biodiversity in areas that may not be suitable for other methods. Determining whether sponges are more effective in capturing the biodiversity of an area over pre-existing methods, however, will require further research, but the authors say this paper is the first step in answering that question. “I am hopeful that this method will prove itself to be useful,” Mariani says. “It’s the quintessential environmentally friendly biodiversity assessment tool.”

The authors acknowledge support from a UK NERC grant.

Whaling, terrible for whales, benefited some birds


This 2017 video says about itself:

Blue whales are the largest animals to have ever existed. Learn why they’re larger than any land animal and why they were hunted for years, making them endangered.

Recently, a Dutch book was published, called Een zee van traan • Vier eeuwen Nederlandse walvisvaart, 1612-1964, by Jaap R. Bruijn and Louwrens Hacquebord. It is about the history of Dutch whaling.

The killing of millions of whales was a disaster for many whale species. However, this meant, the authors say, that some other animal species eating krill, small sea snails or other animals formerly eaten by whales might increase. In the Antarctic, some penguin species did increase. In the Arctic, little auks increased.

This 2015 video from the Arctic says about itself:

Big Trouble for Little Birds | National Geographic

Franz Josef Land is home to 50 species of seabirds. One of them, the little auk, has seen a drop in body mass in recent years. Enric Sala and the Pristine Seas team investigate the possible causes to help save the species.

How Magellanic penguins feed their youngsters


This video says about itself:

Magellanic Penguins on Isla Magdalena, Chile, December 2012

During our trip to South America, we visited the Magdalena Island in Chile. It is a reserve established in 1991, home to more than 150,000 of Magellanic penguins. These penguins make this spot on the shoreline of the Strait of Magellan their home. They return annually to this place between October and March to lay eggs and raise their youngsters.

Magellanic Penguins are often seen performing the “ecstatic display”. This can either be part of the mating ritual or can merely be indicative of territory ownership. Birds performing this display stretch their neck and point their beaks skywards whilst spreading their wings and making a braying noise. The display is often performed repetitively over periods of up to an hour or more.”

From the University of Washington in the USA:

Parents don’t pick favorites, at least if you’re a Magellanic penguin

February 14, 2019

Summary: Researchers wanted to know how Magellanic penguin parents in South America balance the dietary demands of multiple chicks. They found that when a Magellanic penguin parent returns to its nest with fish, the parent tries to feed each of its two chicks equal portions of food, regardless of the youngsters’ differences in age or size.

Parenthood can be a struggle, particularly for families with multiple children in need of care, nurturing, protection and attention. But a weary mom or dad may find solace in the reassurance that all parents with several offspring face a similar challenge — even the non-human variety.

Researchers at the University of Washington wanted to know how Magellanic penguin parents in South America balance the dietary demands of multiple chicks. As they report in a paper published Jan. 23 in the journal Animal Behaviour, when a Magellanic penguin parent returns to its nest with fish, the parent tries to feed each of its two chicks equal portions of food, regardless of the youngsters’ differences in age or size.

This finding surprised the team, since parents across the animal kingdom, including other penguin species, often allocate resources unequally to their chicks based on factors like offspring age, body condition, health and behavior, said senior author P. Dee Boersma. Boersma, a UW professor of biology and director of the Center for Ecosystem Sentinels, has for more than three decades studied penguins at Punta Tombo, a coastal region in Argentina that hosts one of this species’ largest breeding colonies.

“This is an exciting finding because, among animals, it is very unusual for parents to divide food equally among their offspring,” said Boersma. “This makes Magellanic penguin parents stand out not just among penguins, but also animals in general.”

Magellanic chicks are the same size when they hatch, but eggs within a nest hatch at different times. After mating, a Magellanic female lays two eggs about four days apart. One chick typically hatches at least two days before the other. Chicks grow to different sizes based on the timing of their first feedings. By the time both chicks are at least 20 days old, one chick is on average 22 percent heavier than its sibling, the team found. Yet despite these size differences, this study shows that when Magellanic chicks are older and more mobile, parents feed both chicks equally as well as rapidly.

“These findings raise some very interesting evolutionary questions about how and why this behavior — feeding chicks equally — arose,” said Boersma.

For this study, Boersma and her team observed parents feeding their chicks at Punta Tombo from 2003 to 2007. Past research showed that parents alternate roles when chicks are small: One stays at the nest to guard chicks while the other feeds offshore and brings back a belly full of fish to regurgitate into the chicks’ mouths. For this study, the researchers observed nests where the chicks were at least 20 days old to track whether chick behaviors, such as begging or competition during feeding, influenced the amount of food they received. The team weighed 218 chicks both before and after the feeding, and observed parent and offspring behavior during mealtime. Forty chicks came from one-chick nests — presumably cases where the second egg failed to hatch or the chick died of starvation — while the other 178 came from 89 two-chick nests.

As expected, chicks without a sibling received more food during a feeding and were heavier than chicks with a sibling. Before eating, singleton chicks weighed an average of about 5.7 pounds and received about 1.2 pounds of food on average per feeding. For two-chick nests, the heavier and lighter chicks weighed an average of 5.1 pounds and 4.2 pounds, respectively. Yet both chicks received about 0.8 pounds of food on average per feeding.

Parents with two chicks managed this equal division despite the rushed choreography of mealtimes. The researchers found that feedings lasted just 21 minutes on average, during which the parent used its flippers to keep one chick to its left and one to its right — turning its head to feed one and then the other. Light and heavy chicks begged a similar number of times and each switched sides five or six times during the feeding, yet siblings did not act aggressively toward one other. The researchers observed that the parent directed more non-feeding behaviors to the lighter chick, such as opening its mouth but not regurgitating any food. Yet ultimately the lighter chick received the same amount of food as its sibling.

These findings shed light on when, where and how animals decide whether to treat their offspring equally or give preferential attention to one. For Magellanic penguins, factors affecting this behavior may be food supply, digestion and the time between feedings. In other penguin species, food supply impacts feeding behaviors. Adélie penguins, for example, have a relatively stable and abundant food supply because long daylight hours in Antarctic summers allow them to feed around the clock. Boersma and her colleague Lloyd Davis at the University of Otago in New Zealand found that Adélie parents run from their chicks, and the chick that follows its parent the longest is typically fed the most. For Magellanic penguins, food is less plentiful, and chicks typically wait three to five days between feedings. Each year, about 40 percent of chicks die at Punta Tombo due to starvation, and research by Boersma’s group indicates that a chick is most at risk of starvation when it is between 5 and 9 days old. Magellanic parents are prompted feed chicks as soon as they arrive at the nest because food that digests too long in their stomachs is less nutritious for chicks.

These factors may pressure adults to feed chicks quickly and equally, Boersma said. In addition, chicks may avoid direct competition because that could delay the feeding, she added. The age of the chicks in this study — all at least 20 days old — may also help explain their findings.

“This behavior may have evolved because, once both chicks reach this age, it may be advantageous for the parents to try to raise both of their chicks to fledging — the stage at which chicks leave the nest — rather than preferentially giving one more resources than the other,” said Boersma.

If so, then equality on the part of Magellanic penguin parents is less of an egalitarian virtue and more an investment in survival of the next generation.

Penguin evolution influenced by islands


This video is the film March Of The [Emperor] Penguins.

From Molecular Biology and Evolution journal (Oxford University Press):

New islands, happy feet: Study reveals island formation a key driver of penguin speciation

February 5, 2019

Ever since Darwin first set foot on the Galapagos, evolutionary biologists have long known that the geographic isolation of archipelogos has helped spur the formation of new species.

Now, an international research team led by Theresa Cole at the University of Otago, New Zealand, has found the same holds true for penguins. They have found the first compelling evidence that modern penguin diversity is driven by islands, despite spending the majority of their lives at sea.

“We propose that this diversification pulse was tied to the emergence of islands, which created new opportunities for isolation and speciation,” said Cole.

Over the last 5 million years, during the Miocene period, (particularly within the last 2 million years), island emergence in the Southern Hemisphere has driven several branches on the penguin evolutionary tree, and also drove the more recent influence of human-caused extinctions of two recently extinct penguin species from New Zealand’s Chatham Islands.

“Our findings suggest that these taxa were extirpated shortly after human settlement on the Chatham Islands,” said Cole. “These findings thus potentially represent important new examples of human-driven, Holocene extinction in the Pacific.”

“While our results reinforce the importance of islands in generating biodiversity, they also underscore the role of humans as agents of biodiversity loss, especially via the extinction of island-endemic taxa,” said Cole. As many of the bones were from middens, our results provide direct evidence that our newly discovered extinct taxa was hunted by humans.”

The publication appears in the advanced online edition of the journal Molecular Biology and Evolution.

About 20 modern penguin species exist, from the Antarctic emperor penguin, the forest dwelling Fiordland penguin and the tropical Galapagos penguin. A fossil record of more than 50 species can trace back penguin history to more than 60 million years ago — indicating that penguin diversity may have once been much higher than today.

Using historical skin samples and subfossils from natural history museums, along with blood samples, the researchers performed the largest survey to date, across all penguin taxa.

The team tested their island hypotheses using 41 near-complete mitochondrial genomes, representing all extant and recently extinct penguin taxa. They calibrated their mitogenomic evolution to make an evolutionary clock based on the fossil record.

“By using well-justified fossil calibrations, we resolve the timing and mechanisms of modern penguin diversification,” said Cole.

They found that the two largest-bodied and most polar-adapted penguins are sister to all other living penguins. The DNA evidence also showed that genetically similar penguin species may be at the earlies stages of diversification.

The study provides important new data and perspectives to the debate on the origins of penguin diversity. It will also help better understand the role of islands as drivers of speciation to other animals and marine life.

The new taxa have been named Eudyptes warhami and Megadyptes antipodes richdalei after John Warham and Lance Richdale, pioneers in penguin biology.