Planet Earth, 100,000 years ago


This 13 October 2019 video says about itself:

What was our planet like 100,000 years ago? What animals were there? What was the climate like? And which human species were around? Thank you all so much for 100,000 subscribers, it’s unbelievable!

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New big dinosaur species discovered in Thailand


Siamraptor suwati reconstruction

From PLOS:

Meet Siamraptor suwati, a new species of giant predatory dinosaur from Thailand

Siamraptor provides a new glimpse at the early evolution of carcharodontosaurian dinosaurs

October 9, 2019

Fossils discovered in Thailand represent a new genus and species of predatory dinosaur, according to a study released October 9, 2019 in the open-access journal PLOS ONE by Duangsuda Chokchaloemwong of Nakhon Ratchasima Rajabhat University, Thailand and colleagues.

Carcharodontosaurs were a widespread and successful group of large predatory dinosaurs during the Jurassic and Cretaceous Periods and were important members of ecosystems on multiple continents. However, the fossil record of these animals is notably lacking from the Early Cretaceous of Asia, with no definite carcharodontosaurs known from Southeast Asia.

In this study, Chokchaloemwong and colleagues describe fossil material from the Khok Kruat geologic formation in Khorat, Thailand, dating to the Early Cretaceous. These fossils include remains of the skull, backbone, limbs, and hips of at least four individual dinosaurs, and morphological comparison with known species led the authors to identify these remains as belonging to a previously unknown genus and species of carcharodontosaur which they named Siamraptor suwati.

Phylogenetic analysis indicates that Siamraptor is a basal member of the carcharodontosaurs, meaning it represents a very early evolutionary split from the rest of the group. It is also the first definitive carcharodontosaur known from Southeast Asia, and combined with similarly-aged finds from Europe and Africa, it reveals that this group of dinosaurs had already spread to three continents by the Early Cretaceous.

Mother right whales ‘whisper’ to calves


This 2016 video is called North Atlantic Right Whales.

From Syracuse University in the USA:

Hush, little baby: Mother right whales ‘whisper’ to calves

October 9, 2019

Summary: A recent study explores whether right whale mother-calf pairs change their vocalizations to keep predators from detecting them.

On June 20, a whale that researchers had named Punctuation was found dead in the Gulf of Saint Lawrence, a busy international shipping channel. Punctuation — so named for her comma-shaped scars — was a North Atlantic right whale, a species severely threatened by human activity. With only 420 left in the world, it is one of the most endangered whale species. Any additional death, especially of a reproductive female, puts the species further in jeopardy.

News of this death was particularly difficult for Syracuse University biology Professor Susan Parks, who had studied and written about Punctuation in a paper exploring acoustic communication among North Atlantic right whales.

This study was recently published in Biology Letters by Parks, along with Dana Cusano, also of Syracuse; Sofie Van Parijs, Ph.D., of the NOAA Fisheries, Northeast Fisheries Center; and Professor Douglas Nowacek of Duke University. It sheds new light on behavior between mother and calf North Atlantic right whales.

Parks has studied North Atlantic right whale behavior and acoustic communication since 1998. She leads the Bioacoustics and Behavioral Ecology Lab at Syracuse University, whose researchers study the sounds animals make, including those of right whales.

The recent study in Biology Letters explores whether mother-calf pairs change their vocalizations to keep predators from detecting them. Right whales, due to their large size, have few natural predators and are only vulnerable to orca or sharks when they are young calves.

One way to reduce the risk of predation for young calves would be for mothers to hide their young. Because the water is murky, predators are most likely to find right whales by eavesdropping on their communication signals. Any hiding by a mother and her calf would have to be acoustic — that is, producing little or no sound.

Parks and her collaborators studied whether mothers with young calves stop using the usual loud, long-distance communication signals to talk to other right whales. To collect the data, the team listened to whale sounds in the North Atlantic right whale calving grounds off the coasts of Florida and Georgia, using small recording tags attached to the whales by suction cups. Collecting data from mother-calf pairs, and from other juvenile and pregnant whales in the habitat that have less need to hide, the researchers sought to determine if mothers were modifying their behavior to be less conspicuous.

The Biology Letters study shows that mother-calf pairs drastically reduce the production of these common, louder sounds but they also produced a very soft, short, grunt-like sound. These grunts, previously unknown in right whales, were only detectable by the attached recording devices and were not audible more than a short distance from the mother-calf pair.

“These sounds can be thought of almost like a human whisper,” Parks says. “They allow the mother and calf to stay in touch with each other without advertising their presence to potential predators in the area.”

“Right whales face a number of challenges, including a very low number of calves born in recent years combined with a number of deaths from collisions with large ships or entanglement in heavy fishing gear,” Parks says. “There have been 30 confirmed right whale deaths in the past three years, including the recent death of Punctuation in June of this year. There are still so many things we don’t know about their behavior, and it is my hope that studies like these will help to improve efforts for their conservation.”

Big new wasp species discovery in Africa


This August 2018 video is about hornets and wasps.

From the University of Turku:

New large-sized insect species discovered in tropical forest

October 9, 2019

Scientists at the Biodiversity Unit of the University of Turku in Finland have studied the diversity of tropical parasitoid wasps for years. Parasitoid wasps are among the most species rich animal taxa on Earth, but their tropical diversity is still poorly known. Recently, the research group sampled Afrotropical rhyssine wasps, which are among the largest wasps. Scientists from three countries and research institutes participated in the research led by the University of Turku research group.

Rhyssines are sizeable wasps that parasitise the beetle or wasp larvae of decaying wood. The largest species can grow over ten centimetres in length. Females carry an extremely long ovipositor, which is used to drill through wood, stab and paralyse the host, and lay eggs.

Large-sized insect species are usually known better than small species, but tropical rhyssines are an exception.

“A good example of how poorly tropical rhyssines are known is the species Epirhyssa overlaeti, which is the largest African rhyssine. Only two females were known before, one collected in the 1930s in the Congo and the other one in Cameroon in the 1980s. Now, at one single Ugandan site, we found large numbers of both females and males. This completely changed what is known of the distribution of the species,” says Doctoral Candidate Tapani Hopkins from the Biodiversity Unit of the University of Turku, who led the project.

Scientists at the Biodiversity Unit of the University of Turku have previously studied the diversity of rhyssine wasps especially in the Amazonian lowland rainforest.

“In our Amazonian research, we have described ten large-sized South-American species new to science and our understanding of the diversity of South American tropical rainforest parasitoid wasps has changed. Extending the research to the African continent is important, because our goal is to understand the global diversity of the parasitoid insects which are extremely species rich,” says Professor in Biodiversity Research Ilari Sääksjärvi from the Biodiversity Unit of the University of Turku.

In the newest study, two new African tropical parasitoid wasp species were described.

“We named one of the new species Epirhyssa quagga, because its colouration resembles that of a zebra. The other species became Epirhyssa johanna. The name Johanna refers to my wife,” Hopkins says delightedly.

Deep-sea pink octopuses, new research


This 2014 video from the USA says about itself:

Researchers at the Monterey Bay Aquarium Research Institute (MBARI) have observed a deep-sea octopus brooding its eggs for four and one-half years—much longer than any other known animal. Throughout this time, the female kept the eggs clean and guarded them from predators. This amazing feat represents an evolutionary balancing act between the benefits to the young octopuses of having plenty of time to develop within their eggs, and their mother’s ability to survive for years with little or no food. Although long-term observations of deep-sea animals are rare, the researchers propose that extended brooding periods may be common in the deep sea. Such extended life stages would need to be taken into account in assessing the effects of human activities on deep-sea animals. In any case, this strategy has apparently worked for Graneledone (boreo)pacifica—it is one of the most common deep-sea octopuses in the Northeastern Pacific.

Video producer: Susan von Thun
Script and narration: Bruce Robison
Production support: Nancy Jacobsen Stout, Kyra Schlining, Lonny Lundsten, Linda Kuhnz

Scientific paper on this: here.

From the Field Museum in the USA:

The deeper these octopuses live, the wartier their skin

October 8, 2019

Deep beneath the ocean’s surface, surprisingly cute warty pink octopuses creep along the seafloor. But not all these octopuses look alike. While we humans love a good “Is your skin oily, dry, or combination?” quiz, members of one octopus species take variations in skin texture to a whole new level. Some have outrageous warts, while others appear nearly smooth-skinned. Scientists weren’t sure if these octopuses were even members of the same species, and they didn’t know how to explain the differences in the animals’ looks. But in a new study, scientists cracked the case: the deeper in the ocean the octopuses live, the bumpier their skin and the smaller their bodies. DNA revealed even though the octopuses looked different, they were the same species.

“If I had only two of these animals that looked very different, I would say, ‘Well, they’re different species, for sure.’ But variation inside animal species can sometimes fool you,” says Janet Voight, associate curator of zoology at the Field Museum and the lead author of the paper in the Bulletin of Marine Science. “That’s why we need to look at multiple specimens of species to see, does that first reaction based on two specimens make sense?”

To figure out if the smooth and warty octopuses were the same species, the scientists examined 50 specimens that were classified as Graneledone pacifica — the Pacific warty octopus. Plunging deep into the ocean in ALVIN, a human-occupied submersible vehicle, Voight collected some of the octopuses from the Northeast Pacific Ocean. The team also studied specimens loaned from the University of Miami Marine Laboratory and the California Academy of Sciences. They looked at specimens from up and down the Pacific, from as far north as Washington State to as far south as Monterey, California, and from depths ranging from 3,660 feet to more than 9,000 feet below the ocean’s surface.

The researchers counted the number of warts in a line across each octopus’s back and its head and the number of suckers on their arms. They found that the octopuses from deeper in the ocean looked different from their shallower counterparts. The deep-sea specimens were smaller, with fewer arm suckers, and, most noticeably, bumpier skin than those from shallower depths. The thing is, there weren’t two distinct groups; the animals’ appearances changed according to how deep they live. Comparing the octopuses’ DNA sequences revealed only minor differences, supporting the idea that they were all the same species, despite looking so different.

Sometimes when animals look different from each other, scientists can be tempted to jump the gun and declare them separate species — especially in the deep sea, where very little is known about animal life and scientists often don’t have many specimens to compare. But looking different doesn’t necessarily mean that animals are members of different species; take chihuahuas’ and Great Danes’, which are both the same species of Canis lupus familiaris, dogs, different appearances are due to selective breeding by humans, but in the case of the warty octopuses in this study, their different appearances seem to result from environmental influences, because their appearance changes depending on where the octopuses are from.

Scientists aren’t sure why the variations in skin texture occur with depth. But they do have a hunch about the size difference.

Voight thinks that these octopuses usually eat creatures from the sediment on the ocean floor, passing food from sucker to sucker and then crushing their prey like popcorn. “There’s less food as you get deeper in the ocean. So these animals have to work harder to find food to eat. And that means at the end of their lives, they’ll be smaller than animals who have more food. If you’re a female who’s going to lay eggs at the end of your life, maybe your eggs will be smaller” says Voight. Smaller eggs mean smaller hatchlings.

Support for this hypothesis comes from the number of suckers on the males’ arm that transfers sperm packets to females. Earlier research by Voight found that male hatchlings have a full-formed arm with all its suckers in place. The researchers documented that the number of suckers on this arm was way smaller in males from greater depth, and Voight hypothesizes it relates to egg size.

“The octopus hatchlings in shallower water, only 3,660 feet, are bigger. Their eggs had more yolk. As the embryos grew, they developed farther inside the egg than the ones from 9,000 feet, who were developing in smaller eggs. They had less energy to fuel their growth before they left the egg, so they made fewer suckers,” says Voight. Seeing these physical manifestations of octopuses’ food limitation provides a hint of how they might fare as climate change progresses and the octopuses’ food supply fluctuates.

Voight notes that this study, which shows that different-looking octopuses can still be the same genetic species, could help researchers down the line trying to identify life forms in the deep sea. Remotely operated vehicles collect video footage of the ocean floor, and it can be used to estimate the number of species present — if we know what they look like. That’s why, Voight says, it’s so important to examine specimens in person and use characteristics you can’t see on video to identify species boundaries.

“There’s still just so much we don’t know about the deep sea. We need to be able to understand the information that’s becoming available from ROV footage. And we can only do it by knowing what the animals look like.”

Invertebrate fossils discovery in Dominican Republic amber


Sialomorpha dominicana

From Oregon State University in the USA:

Meet the ‘mold pigs,’ a new group of invertebrates from 30 million years ago

October 8, 2019

Fossils preserved in Dominican amber reveal a new family, genus and species of microinvertebrate from the mid-Tertiary period, a discovery that shows unique lineages of the tiny creatures were living 30 million years ago.

The findings by George Poinar Jr. of the Oregon State University College of Science give a rare look at a heretofore unknown clade of invertebrates, along with their fungal food source and other animals that lived in their habitat.

Poinar, an international expert in using plant and animal life forms preserved in amber to learn more about the biology and ecology of the distant past, informally calls the new animals “mold pigs” for their resemblance to swine, and their diet. Scientifically, they are Sialomorpha dominicana, from the Greek words for fat hog (sialos) and shape (morphe).

Invertebrate means not having a backbone, and invertebrates account for roughly 95 percent of animal species.

“Every now and then we’ll find small, fragile, previously unknown fossil invertebrates in specialized habitats,” Poinar said. “And occasionally, as in the present case, a fragment of the original habitat from millions of years ago is preserved too. The mold pigs can’t be placed in any group of currently existing invertebrates — they share characteristics with both tardigrades, sometimes referred to as water bears or moss pigs, and mites but clearly belong to neither group.”

The several hundred individual fossils preserved in the amber shared warm, moist surroundings with pseudoscorpions, nematodes, fungi and protozoa, Poinar said.

“The large number of fossils provided additional evidence of their biology, including reproductive behavior, developmental stages and food,” he said. “There is no extant group that these fossils fit into, and we have no knowledge of any of their descendants living today. This discovery shows that unique lineages were surviving in the mid-Tertiary.”

The Tertiary period began 65 million years ago and lasted for more than 63 million years.

About 100 micrometers long, the mold pigs had flexible heads and four pairs of legs. They grew by molting their exoskeleton and fed mainly on fungi, supplementing that food source with small invertebrates.

“No claws are present at the end of their legs as they are with tardigrades and mites,” Poinar said. “Based on what we know about extant and extinct microinvertebrates, S. dominicana appears to represent a new phylum. The structure and developmental patterns of these fossils illustrate a time period when certain traits appeared among these types of animals. But we don’t know when the Sialomorpha lineage originated, how long it lasted, or whether there are descendants living today.”