Californian sea otters and archaeology


This September 2018 says about itself:

Cute Sea Otter Behaviour Decoded

From holding paws to rubbing their faces, sea otters are otter-ly adorable. But why do they do it? Discover the science behind the cute.

From the Max Planck Institute for the Science of Human History in Germany:

Sea otters’ tool use leaves behind distinctive archaeological evidence

Researchers used an interdisciplinary approach combining ecology and archaeological methods to study sea otters’ past behavior

March 14, 2019

An international team of researchers has analyzed the use by sea otters of large, shoreline rocks as “anvils” to break open shells, as well as the resulting shell middens. The researchers used ecological and archaeological approaches to identify patterns that are characteristic of sea otter use of such locations. By looking at evidence of past anvil stone use, scientists could better understand sea otter habitat use.

Sea otters are an especially captivating marine mammal, well known for their use of rocks to break open shells. Sea otters are estimated to have once numbered between 150,000-300,000 individuals and their range stretched from Baja California, Mexico, around the northern Pacific Rim to Japan. Their numbers were dramatically reduced by the fur trade. In California, the southern sea otter population was reduced to around 50 individuals, but a massive conservation effort has resulted in increasing their numbers to around 3000 today. However, the southern sea otter is still considered threatened.

Sea otters are unique for being the only marine mammal to use stone tools. They often use rocks to crack open shells while floating on their back, and also sometimes use stationary rocks along the shoreline as “anvils” to crack open mollusks, particularly mussels. A joint project including the Max Planck Institute for the Science of Human History, the Monterey Bay Aquarium and the University of California, Santa Cruz, among others, has resulted in a first-of-its-kind interdisciplinary study published in Scientific Reports, combining ten years of observations of sea otters with archaeological methods to analyze sea otter use of such anvil stones, also known as emergent anvils.

Sea otter use of anvil stones leaves distinctive wear and shell middens that are characteristic of sea otters

Researchers spent ten years between 2007-2017 observing sea otters consuming mussels at the Bennett Slough Culverts site in California. Their analysis identified that mussels were the most common prey eaten at the site and were the only prey for which the sea otters used stationary anvil stones. The sea otters used such stones for about 20% of the mussels they consumed.

Interestingly, careful analysis of the stationary anvil stones using archaeological methods showed that their use resulted in a recognizable damage pattern that was distinguishable from what would be caused by human use. For example, the sea otters preferentially struck the mussels against points and ridges on the rocks, and struck the rocks from a position in the water, rather than from the land or from on top of the rock.

Consistent damage pattern on broken mussel shells indicates probable “pawedness” in sea otters

In addition to the stones themselves, the researchers also carefully analyzed the mussel shells left around the stationary anvils. The researchers took a random sample of the shell fragments from these shell middens, which likely contained as many as 132,000 individual mussel shells. They found an extremely consistent damage pattern, with the two sides of the mussel shell still attached, but a diagonal fracture running through the right side of the shell.

“The shell breakage patterns provide a novel way to distinguish mussels broken by sea otter pounding on emergent anvils from those broken by humans or other animals,” explains Natalie Uomini of the Max Planck Institute for the Science of Human History. “For archaeologists who excavate past human behavior, it is crucial to be able to distinguish the evidence of sea otter food consumption from that of humans.”

In combination with analysis of videos they took of the otters using the anvils, researchers could see that the otters held the shells evenly in both paws, but when striking the shell against the anvil tended to have their right paw slightly on top. Though the total number of otters observed was small, these results suggest that otters may exhibit handedness, or “pawedness,” as do humans and many other mammals.

Potential for archaeological investigations of past sea otter behavior

The researchers hope that the study will be useful for archaeologists working with coastal populations, as a way to distinguish between human and sea otter use of rocks and consumption of marine resources. Additionally, the research could be helpful in future studies of the geographic spread of stationary anvil use throughout the former sea otter range, and how far into the past this behavior extends.

“Our study suggests that stationary anvil use can be detected in locations previously inhabited by sea otters. This information could help to document past sea otter presence and diet in locations where they are currently extirpated,” explains Jessica Fujii of the Monterey Bay Aquarium.

“More broadly,” she adds, “the recovery of past animal behavioral traces helps us to understand the evolution of behaviors like stone anvil use, which is rare in the animal kingdom and is extremely rare in marine animals. We hope that this study establishes a new path for the growing field of animal archaeology.”

Sea otters have very low genetic diversity, scientists report. Their findings have implications for the conservation of rare and endangered species, in which a lack of genetic diversity can increase the risk of extinction: here.

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How wild apes react to camera traps


This November 2013 video says about itself:

Apes of East Africa

Tracking chimpanzees in Tanzania and mountain gorillas in Rwanda.

From the Max Planck Institute for Evolutionary Anthropology in Germany:

Wild African ape reactions to novel camera traps

African wild apes notice and often react to novel items in their environment

March 14, 2019

An international team of researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed video from remote camera-trap devices placed in ape-populated forests throughout Africa to see how wild apes would react to these unfamiliar objects. Responses varied by species, and even among individuals within the same species, but one thing was consistent throughout: the apes definitely noticed the cameras.

“Our goal was to see how chimpanzees, bonobos, and gorillas react to unfamiliar objects in the wild since novel object experiments are often used in comparative psychology research, and we wanted to know if there were any differences among the three great apes,” says Ammie Kalan, a primatologist at the Max Planck Institute for Evolutionary Anthropology. “We were specifically surprised by the differences in reactions we observed between the chimps and bonobos. Since they’re sister species and share a lot of the same genetic makeup, we expected them to react similarly to the camera, but this wasn’t the case.”

“The chimpanzees were overall uninterested in the camera traps — they barely seemed to notice their presence and were generally unbothered by them,” Kalan says. “Yet the bonobos appeared to be much more troubled by camera traps; they were hesitant to approach and would actively keep their distance from them.”

Individuals within a species reacted differently to the cameras as well. For example, apes living in areas with more human activity, such as near research sites, can get desensitized to unfamiliar items and become indifferent toward such encounters in the future. However, another member of the same species who has had less exposure to strange or new items, might be more interested in them. The age of the ape plays a similar role. “Younger apes would explore the camera traps more by staring at them for longer periods of time,” Kalan says. “Like human children, they need to take in more information and learn about their environment. Being curious is one way of doing that.”

The range of responses shown by the apes, and the complex differences both between species and within a single species, demonstrates a need for scientists to consider how animals will respond to the presence of unfamiliar monitoring equipment in their natural habitats. “The within and between species variation in behavior towards the unfamiliar items might be problematic when trying to collect accurate monitoring data,” Kalan says. “To curb this effect, it would be worth having a familiarization period, where the wild animals can get used to the new items.”

Despite this potential complication, using camera traps to monitor populations of animals in the wild is still one of the most useful options. “Our knowledge tends to be limited by the number of groups or number of populations we’re able to study, but using monitoring technology like camera traps is an effective way of solving that problem,” Kalan says. “I think it’s really interesting from a behavioral flexibility perspective to consider how wild animals react to these new technologies. I would love for more researchers to investigate novelty responses while doing monitoring surveys.”

Striking pro-climate students march in Amsterdam


This 14 March 2019 video shows striking pro-climate students marching in Amsterdam, the Netherlands today.

Pro-climate march in Amsterdam, 14 March 2019, ANP photo

One of the signs on this photo of the march says, translated: If the climate would be money, then the world would have been saved already.

One of the students interviewed by the Dutch NOS TV said that governments spend billions on bailing out banks, while doing little against climate change.

This video shows the march.

Translated from NOS TV today:

Thousands of high school students were in Amsterdam this afternoon to demonstrate for a better climate policy. They marched from the Dam square to the Museumplein square. …

The government’s climate plans were calculated yesterday and the most important conclusion was that it would be difficult to achieve the CO2 reduction targets. In the afternoon the government made changes, announcing, eg, a CO2 tax for corporations.

Which the right-wing government had refused earlier, as they love corporations and their profits.

“Take action now”

The students are not reassured that the plans will turn out well. “It is important that we have a good future, that the earth does not get warmer”, says a student with a sign Make Earth Cool Again on it. Another student points out that Prime Minister Rutte has not said how high the CO2 tax will be. “It is important that it becomes enough, we protest to achieve that.” …

Another girl on strike interviewed by the NOS said that corporations may try to dodge the CO2 tax.

This tweet is about the fat cats of Shell corporation who cause much of the climate change.

Many students say that they have received permission from their schools to go to the demonstration. …

The students announced that they would once again march on 24 May during a European day of action.

And on 25 April, there will be a students’ pro-climate strike as well; as this tweet shows.

In Belgium, some schools oblige their pupils to join the climate march tomorrow. It then counts as extracurricular activity.

There will be a big march in Brussels and more marches in 24 other Belgian cities and towns tomorrow.

This tweet is from Scotland.

And this one is from Kenya.

French state faces landmark lawsuit over climate inaction: here.

Gull drops mussel on rock


This 14 December 2018 video shows a young gull dropping a mussel from the sky to break the shell on a hard rock, in order to be able to feed on its contents. At the end of the video, a turnstone.

Martien van Beekveld made the video on the Brouwersdam causeway in the Netherlands. He saw more gulls doing this.

It is a bit like bearded vultures dropping bones from the sky on rocks, to be able to feed on the marrow inside the bones.

Belgian cardinal Godfried Danneels dies


This 11 September 2010 video by Australian broadcasting organisation ABC says about itself:

Pedophile Horrors in Belgium In Church, Politics, Social Services

No congregation escaped Belgian sex abuse. “It’s the Church’s Dutroux”, referring to mid-1990s trauma in Belgium + arrest of serial rapist / child killer Marc Dutroux, serving life for six rapes and four murders.

Read more here.

The video is also about the ‘Legionaries of Christ‘, an international Roman Catholic order, founded by a pedophile priest with close connections to Pope John Paul II.

Translated from Belgian (Roman Catholic) daily De Standaard today:

Cardinal Godfried Danneels, Archbishop Emeritus of Mechelen-Brussels, died Thursday morning in Mechelen. Cardinal Jozef De Kesel reports this. Danneels was 85 years old. …

The role that Danneels played in the abuse case of Bruges bishop Roger Vangheluwe in 2010 is a blot on his career. Recorded conversations that Danneels had with Vangheluwe and a victim showed that Danneels had tried to cover up the affair.

The Standaard might have added the discovery during a police raid in Danneels’ archiepiscopal palace of secret photos about the scandal of Belgian child rapist and murderer Marc Dutroux.