Brazilian river dolphins communication, new study


This 2014 video says about itself:

A new species of river dolphin has been discovered by scientists working in Brazil. This is the fifth known species of its kind, and there are an estimated one thousand of the dolphins living in the Araguaia river basin.

Researchers from the Federal University of Amazonas ran genetic testing on some of the dolphins to be certain that a new species had been found. The last time a new species of river dolphin was discovered was back in 1918.

Doctor Tomas Hrbek, lead author of the study, is quoted as saying: “It is very similar to the other ones. It was something that was very unexpected, it is an area where people see them all the time, they are a large mammal, the thing is nobody really looked.” The Araguaia dolphins are smaller and reportedly have fewer teeth than the Amazon river dolphins, also called boto or pink dolphins, which are believed to be the most intelligent of the river dolphins.

From the University of Vermont in the USA:

Mysterious river dolphin helps crack the code of marine mammal communication

April 19, 2019

The Araguaian river dolphin of Brazil is something of a mystery. It was thought to be quite solitary, with little social structure that would require communication. But Laura May Collado, a biologist at the University of Vermont, and her colleagues have discovered that the dolphins can actually make hundreds of different sounds to communicate, a finding that could help uncover how communication evolved in marine mammals.

“We found that they do interact socially and are making more sounds than previously thought,” she says. “Their vocal repertoire is very diverse.”

The findings of May Collado are her colleagues were published in the journal PeerJ on April 18.

The Araguaian dolphins, also called botos, are a difficult animal to study. They are hard to find in the first place, and while the waters of the Araguaia and Tocatins rivers are clear, it is challenging to identify individuals because the dolphins are skittish and hard to approach.

Luckily, Gabriel Melo-Santos, a biologist from the University of St Andrews in Scotland and leader of the project, found a fish market in the Brazilian town of Mocajuba where the botos regularly visit to be fed by people shopping there. The clear water and regular dolphin visits provided a unique opportunity to get a close look at how the animals behave and interact, and to identify and keep track of various individuals.

The team used underwater cameras and microphones to record sounds and interactions between the dolphins at the market, and took some genetic samples. They identified 237 different types of sounds the dolphins make, but even with 20 hours of recordings the researchers don’t believe they captured the animals’ entire acoustic repertoire. The most common sounds were short, two-part calls that baby dolphins made when they were approaching their mothers.

“It’s exciting; marine dolphins like the bottlenose use signature whistles for contact, and here we have a different sound used by river dolphins for the same purpose,” says May Collado. The river dolphins also made longer calls and whistles, but these were much rarer, and the reasons for them are not yet clear. But there is some indication that whistles serve the opposite purpose than in bottlenose dolphins, with the botos using them to maintain distance rather than for group cohesion.

The acoustic characteristics of the calls are also interesting; they fall somewhere between the low-frequency calls used by baleen whales to communicate over long distances, and the high-frequency ones used by marine dolphins for short distances. May Collado speculates that the river environment may have shaped those characteristics.

“There are a lot of obstacles like flooded forests and vegetation in their habitat, so this signal could have evolved to avoid echoes from vegetation and improve the communication range of mothers and their calves,” she says.

May Collado and her colleagues next want to study whether the same diversity of communication is seen in other populations of Araguaian river dolphins that are less accustomed to humans, and compare them to their relatives elsewhere in South America. The Araguaian dolphins are closely related to two other species, the Bolivian river dolphin and Amazon river dolphin; the Araguaian dolphins were only described as a separate species in 2014, and that classification is still under debate. But there seems to be a large amount of variation in the repertoire of sounds each species makes.

The Amazon dolphins in Ecuador, studied by May Collado in 2005, are generally very quiet. “We need more information on these other species and more populations,” she says. “Why is one population chattier than others and how do these differences shape their social structure?”

May Collado says the work could help researchers gain clearer understanding of how communication evolved in marine mammals. Similar calls have been reported in pilot whales and killer whales, for example, and the similarities and differences between different species could help tease out which signals evolved first, and why.

The river dolphins are evolutionary relics, represented by just a few species around the world, and they diverged from other cetaceans much earlier than other dolphins. So these calls may have arisen first in river dolphins, then later evolved in marine dolphins into whistles and calls but in a different social context. Or was there a change in the function of the calls, with this kind of sound being used for group identity in killer whales, and individual identity in river dolphins? The calls may also have other functions in addition to identity, perhaps indicating group identity, or providing information on emotional state.

“We can’t say what the evolutionary story is yet until we get to know what sounds are produced by other river dolphins in the Amazon area, and how that relates to what we found,” she says. “We now have all these new questions to explore.”

Advertisements

Saving butterflies with computer games


This 26 June 2014 video from the USA says about itself:

UF/IFAS entomologists are trying to save an endangered butterfly found only in Florida by breeding a captive colony of Schaus’ Swallowtail Butterflies. The goal is release these captive butterflies back into wild to breed and help bring this insect back from the brink of extinction.

From ScienceDaily:

Living room conservation: Gaming and virtual reality for insect and ecosystem conservation

Players explore and search for butterflies using knowledge gained through gameplay

April 18, 2019

Gaming and virtual reality (VR) could bridge the gap between urban societies and nature, thereby paving the way to insect conservation by the means of education, curiosity and life-like participation.

This is what Florida International University’s team of computer scientist Alban Delamarre and biologist Dr Jaeson Clayborn strive to achieve by developing a VR game dedicated to insect and plant species. Focused on imperiled butterflies, their innovative idea: Butterfly World 1.0, is described in the open-access journal Rethinking Ecology.

This February 2019 video is called Butterfly World 1.0 Intro Video.

Butterfly World 1.0 is an adventure game designed to engage its users in simulated exploration and education. Set in the subtropical dry forest of the Florida Keys (an archipelago situated off the southern coast of Florida, USA), Butterfly World draws the players into an immersive virtual environment where they learn about relationships between butterflies, plants, and invasive species. While exploring the set, they interact with and learn about the federally endangered Schaus’ swallowtail butterfly, the invasive graceful twig ant, native and exotic plants, and several other butterflies inhabiting the dry forest ecosystem. Other nature-related VR experiences, including conservation awareness and educational programs, rely on passive observations with minimal direct interactions between participants and the virtual environment.

According to the authors, virtual reality and serious gaming are “the new frontiers in environmental education” and “present a unique opportunity to interact with and learn about different species and ecosystems.”

The major advantage is that this type of interactive, computer-generated experience allows for people to observe phenomena otherwise impossible or difficult to witness, such as forest succession over long periods of time, rare butterflies in tropical dry forests, or the effects of invasive species against native wildlife.

“Imagine if, instead of opening a textbook, students could open their eyes to a virtual world. We live in a time where experiential learning and stories about different species matter, because how we feel about and connect with these species will determine their continued existence in the present and future. While technology cannot replace actual exposure to the environment, it can provide similar, near-realistic experiences when appropriately implemented,” say the scientists.

In conclusion, Delamarre and Clayborn note that the purpose of Butterfly World is to build knowledge, reawaken latent curiosity, and cultivate empathy for insect and ecosystem conservation.

Fish warn others chemically about dangers


This june 2013 video is called Fathead minnows in my pond.

From the University of Saskatchewan in Canada:

Fish under threat release chemicals to warn others of danger

April 18, 2019

Fish warn each other about danger by releasing chemicals into the water as a signal, research by the University of Saskatchewan (USask) has found.

The USask researchers discovered that wild fish release chemicals called ‘disturbance cues’ to signal to other fish about nearby dangers, such as predators.

The findings may have implications for fish conservation efforts across the globe.

“Disturbance cues may help to explain why some fish populations crash after they decline past a certain point,” said Kevin Bairos-Novak, a graduate student member of the research team.

While researchers have been aware that fish release chemicals into the water for 30 years, this is the first time their use has been studied.

The findings, involving researchers from the USask biology department and the Western College of Veterinary Medicine, are published in the Journal of Animal Ecology.

Fish signaled most when in the presence of familiar fish, but signaled far less or not at all when in the presence of strangers, or when on their own.

The signals provoked a ‘fright response’ in fish they knew, including freezing, dashing about and then shoaling tightly together. Fish use this behavior to defend themselves against predators.

“When minnows

The research is about fathead minnows. They live in North America.

were present alongside familiar minnows, they were much more likely to produce signals that initiated close grouping of nearby fish, a strategy used to avoid being eaten by predators,” said Bairos-Novak, who is now at James Cook University, Australia.

Disturbance cues are voluntarily released by prey after being chased, startled or stressed by predators.

One of the main constituents of the signal is urea, found in fish urine.

Fathead minnows, caught at a lake, were placed in groups with familiar fish, unfamiliar fish or as isolated individuals. The research team then simulated a predator chase. The fish responded by shoaling, freezing and dashing when they received a signal from a group they knew. But they did not take significant defensive action when receiving cues from unfamiliar fish or isolated minnows.

Disturbance cues are voluntarily released by prey after being chased, startled or stressed by predators.

“It is exciting to discover a new signaling pathway in animals,” said Maud Ferrari, Bairos-Novak’s supervisor and a behavioural ecologist in the veterinary college’s Department of Veterinary Biomedical Sciences. “We found that fish are able to manipulate the behaviour of other individuals nearby by issuing a signal.”

The research was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC).

Anti-Christian terrorism in Sri Lanka at Easter


This 21 April 2019 video is called At least 280 injured in multiple blasts at churches & hotels in Sri Lanka.

From the Economic Times in India:

Sri Lanka Blasts Live Updates: 129 dead, over 400 injured in six explosions on Easter

Serial blasts occurred at around 8.45 am as the Easter Sunday masses were in progress in churches

Updated: Apr 21, 2019, 12.26 PM IST

Other sources claim at least 160 dead.

With all of my heart, I wish strength and recovery to the survivors of these terrible crimes.

At least 129 people were killed and more than 400 other injured after six near simultaneous blasts hit three Sri Lankan churches and three five-star hotels on Easter Sunday. These are the first major attacks since the end of the civil war 10 years ago. According to local reports, the blasts in hotels and churches in different parts of the country occurred at around 8.45 am (local time) as the Easter Sunday masses were in progress in churches.

* In just one church, St. Sebastian’s in Katuwapitiya Colombo, more than 50 people had been killed.

* Media reported 25 people were also killed in an attack on a church in Batticaloa in Eastern Province.

* At least nine foreigners dead in the blasts

* Nobody has claimed responsibility for the attacks yet in a country which was at war for decades with Tamil separatists until 2009 during which bomb blasts in the capital were common.

So we don’t know yet which apparently terrorist group committed these crimes.

Tamils? Improbable, as this mostly Hindu minority group suffer from extremist Buddhist violence and would not probably attack other minorities.

Sri Lanka Muslims? Also improbable, as this minority group also suffers from extremist Buddhist violence and would not probably attack other minorities.

If this would have happened in Iraq, then I would guess that the perpetrators were most probably violent extreme Muslims, unleashed by George W Bush’s 2003 invasion of Iraq.

However, Sri Lanka is not Iraq; and the situation of all religious groups is not the same all over the world. A creed which is a state religion in country A may be a persecuted minority in country B.

There are violent fringes in probably all religions, whose violence is rejected by non-violent co-religionists.

In, eg, the USA, New Zealand and Europe, there are violent self-styled Christians attacking Jews and Muslims; and sometimes Sikhs and Hindus.

In India, violent self-styled Hindus attack Muslims, Christians, atheists and Buddhists.

Though most Buddhists are peace-loving people, there is an extremist fringe among them as well. In Myanmar, a monk calls himself ‘the Buddhist Bin Laden’ and instigates violence against the Rohingya Muslim minority.

So, we don´t know yet who today’s perpetrators are. As religious violence is most often by violent fringe people of majority religions in their countries, this might be extremist Buddhist violence. Like there has been earlier in Sri Lanka against Hindus and against Muslims.

One should hope that the Sri Lankan government will not abuse this terrible bloodbath as a pretext for attacking civil liberties, like other governments did after criminal acts.

However, it seems like the Sri Lankan government has announced a curfew and blocked social media. It does not seem to work yet.

Galapogos giant tortoises and climate change


This 23 March 2019 video says about itself:

Tracking Giant Galapagos Tortoises | BBC Earth

From the Ecological Society of America:

Giant tortoises migrate unpredictably in the face of climate change

Unlike many migratory species, Galapagos giant tortoises do not use current environmental conditions to time their seasonal migration

April 18, 2019

Summary: Researchers use GPS to track the timing and patterns of giant tortoise migration over multiple years. The tortoises often take the same migration routes over many years in order to find optimal food quality and temperatures. The timing of this migration is essential for keeping their energy levels high, and climate change could disrupt a tortoise’s ability to migrate at the right time.

Galapagos giant tortoises, sometimes called Gardeners of the Galapagos, are creatures of habit. In the cool dry season, the highlands of the volcano slopes are engulfed in cloud which allows the vegetation to grow despite the lack of rain. On the lower slopes, however, there is no thick fog layer, and vegetation is not available year round. Adult tortoises thus spend the dry season in the higher regions, and trek back to the lower, relatively warmer zones where there is abundant, nutritious vegetation when the rainy season begins.

The tortoises often take the same migration routes over many years in order to find optimal food quality and temperatures. The timing of this migration is essential for keeping their energy levels high, and climate change could disrupt a tortoise’s ability to migrate at the right time.

In the Ecological Society of America’s journal Ecology, researchers use GPS to track the timing and patterns of tortoise migration over multiple years.

“We had three main goals in the study,” says Guillaume Bastille-Rousseau, lead author of the paper. “One was determining if tortoises adjust their timing of migration to current environmental conditions. Two, if so, what clues do they use to adjust the timing, and, three, what are the energetic consequences of migration mis-timing for tortoises?”

The researchers expected the migrations to be timed with current food and temperature conditions because many other migratory species operate that way. Bastille-Rousseau says “many animals, such as ungulates, can track current environmental conditions and migrate accordingly — what researchers sometime refer to as surfing the green-wave.”

Contrary to the researchers’ expectations, however, migration is weakly associated with current conditions such as fog, rain, and temperature. For instance, if it is unseasonably arid, it appears the tortoises do not take that variation into account when deciding it is time to migrate. It is unclear at this point whether they are basing their migration decisions on memories of past conditions or if they are simply incorrectly assessing current local conditions.

Bastille-Rousseau says the team is surprised by the mismatch, stating “tortoise timing of migration fluctuated a lot among years, often by over two months. This indicates that migration for tortoises may not just be about foraging opportunities. For example, female tortoises have to make decisions related to nesting, and we still have a lot to learn about migration in giant tortoises.”

Fortunately, this sub-optimal timing may not yet have critical impact on tortoise health. Potentially due to their long lives of up to 100 years and large body size, bad timing of migration has smaller consequences for giant tortoises compared to small, short lived animals. Giant tortoises can go up to a year without eating and survive, while other migrating species must eat more regularly to sustain their energy levels.

Giant tortoises are important ecosystem engineers in the Galapagos, responsible for long-distance seed dispersal, and their migration is key for many tree and plant species’ survival. How the tortoises’ variation in migration timing will affect the rest of the ecosystem is still unclear. Because tortoises do not seem to be tracking annual variation in environmental conditions, it is quite possible that the mistiming of migration will keep increasing in the future.

“One concern is that at some point in the future,” Bastille-Rousseau adds, “migration may not be an optimal strategy for tortoises. There may be a reduction in the number of individuals doing these long-distance movements. This would likely have cascading consequences for the whole ecosystem.”

THE CLIMATE KIDS ARE ALL RIGHT The last five years were the five hottest on record. The amount of carbon dioxide in the atmosphere has soared past 410 parts per million. As many as 150 species die off each day. As the call for action grows louder, the youth climate movement ― which scientists say has moved the needle on action to address the climate emergency ― is taking center stage. [HuffPost]

HAWAII BEACHES MAY SOON BE UNDERWATER Hawaii’s iconic Waikiki Beach could soon be underwater as rising sea levels caused by climate change overtake its white sand beaches and bustling city streets. State lawmakers are trying to pass legislation that would spend millions for a coastline protection program. [AP]

A new Stanford University study shows global warming has increased economic inequality since the 1960s. Temperature changes caused by growing concentrations of greenhouse gases in Earth’s atmosphere have enriched cool countries like Norway and Sweden, while dragging down economic growth in warm countries such as India and Nigeria: here.