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.

Neanderthals and art, videos


This 9 October 2019 video says about itself:

There is a huge debate around whether and to what extent Neanderthals made art. Here to help me set the record straight is Dr. Wragg Sykes, Neanderthal expert, archaeologist and author.

Sites mentioned in the interview:

Bruniquel Cave, France

Cioarei-Borosteni, Romania

Fumane Cave, Italy

This video is about the Bruniquel cave.

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.