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Wild bees have found a surprising place to nest in cities

New Scientist Feed - Tue, 09/03/2024 - 7:00am
A survey found 66 species of insects making their homes in cobbled pavements on the streets of Berlin, and greater biodiversity near insect-friendly flower gardens
Categories: Science

Marmosets Call Each Other By Name

neurologicablog Feed - Tue, 09/03/2024 - 5:00am

Humans identify and call each other by specific names. So far this advanced cognitive behavior has only been identified in a few other species, dolphins, elephants, and some parrots. Interestingly, it has never been documented in our closest relatives, non-human primates – that is, until now. A recent study finds that marmoset monkeys have unique calls, “phee-calls”, that they use to identify specific individual members of their group. The study also found that within a group of marmosets, all members use the same name to refer to the same individual, so they are learning the names from each other. Also interesting, different families of marmosets use different kinds of sounds in their names, as if each family has their own dialect.

In these behaviors we can see the roots of language and culture. It is not surprising that we see these roots in our close relatives. It is perhaps more surprising that we don’t see it more in the very closest relatives, like chimps and gorillas. What this implies is that these sorts of high-level behaviors, learning names for specific individuals in your group, is not merely a consequence of neurological develop. You need something else. There needs to be an evolutionary pressure.

That pressure is likely living in an environment and situation where families members are likely to be out of visual contact of each other. Part of this is the ability to communicate at long enough distance that will put individuals out of visual contact. For example, elephants can communicate over miles. Dolphins often swim in murky water with low visibility. Parrots and marmosets live in dense jungle. Of course, you need to have that evolutionary pressure and the neurological sophistication for the behavior – the potential and the need have to align.

There is also likely another element – the quirkiness of evolution. Not all species will find the same solution to the same problem. Many animals evolve innate calls that they use to communicate to their group – such as warnings that a predator is near, or a summons that they have found food. But very few have hit upon the strategy of adjusting those calls to represent specific individuals.

The researchers hope that this one puzzle piece will help them investigate the evolution of human language. I find this a fascinating topic, but it’s one that is difficult to research. We have information going back preserved in writings, which go back about 5,400 years. We have extant cultural knowledge as well – the languages that people around the world speak today. But that’s it, a window going back about 5 thousand years. We also have information from our closest relatives – the uses of language and the language potential is non-human primates. This can give us a somewhat complicated window into the evolution of human language, but this picks up with our last common ancestor about 8 million years ago (with a wide range of uncertainty).

In between these two time periods, when all the interesting stuff was happening, we have almost no information. We have cave painting going back tens of thousands of years, and these give us some insight into the intellectual world of our ancestors, but not directly into their language. We can study hominid anatomy, to see if their larynxes were optimized for human speech. Only Homo sapiens have a “modern” vocal tract. Neanderthals were close but had some specific differences which likely meant their vocal range was lower than modern humans. But this does not mean that our older ancestors could not communicate vocally. Some researchers argue that primates have had sufficient vocal anatomy for some speech going back 27 million years.

But again, this gives us scant information about the evolution of language itself. Most of what we know comes from examining the direct evidence of actual language, from the last few thousand years. We can still learn a lot from this, from studying what different languages have in common, how they are structured, and their internal logic. We can also investigate the neurological correlates of language, and there are ways to disentangle which components of language are evolved (wired in the brain) and which are cultural and learned.

Once concept I find interesting is that of embodied cognition. We use a lot of words to represent abstract ideas that are metaphors for physical relationships. A boss is “above” their employee, but not literally physically above them. Ideas can be “deep”, and arguments can be “strong” or “weak”. This makes some evolutionary sense. Things evolve generally from simpler but fully functional forms. They do not evolve directly to their modern complexity. The eye evolved from simpler forms, but ones that were fully functional for what they did.

Similarly it is likely language evolved from simpler vocal communication, but ones that functioned. What is especially interesting about language is that language also relates to cognition. The two may have evolved hand-in-hand. First we developed sounds for the concrete things in our world, then for features of those concrete things. At some point there was a cognitive breakthrough – the metaphor. This stone is rough and it hurts to rub it. Your behavior is also “rough” and “hurts”. What’s interesting to think about is which came first, the idea or the word. Or did they crystalize together? Likely there was some back and forth, with ideas pushing language forward, which in turn pushed ideas forward. Language and ideas slowly expanded together. This resulted in a cognitive explosion that separates us from all other animals on Earth.

The elements that lead to this explosion can be found in our ancestors. But only in humans did they all come together.

The post Marmosets Call Each Other By Name first appeared on NeuroLogica Blog.

Categories: Skeptic

Huge asteroid impact may have knocked over Jupiter's largest moon

New Scientist Feed - Tue, 09/03/2024 - 3:00am
Ganymede, the largest moon in the solar system, has signs of an enormous ancient impact that would have redistributed its mass, changing its orientation in relation to Jupiter
Categories: Science

Skeptoid #952: Finding Slumach's Gold

Skeptoid Feed - Tue, 09/03/2024 - 2:00am

Is this just another in a long line of legendary lost mines that never produced a speck of gold, or is there more to it this time?

Categories: Critical Thinking, Skeptic

Quoth Myrna Mantaring: “US government data” confirms a “143,233% increase in cancer cases due to COVID vaccination”? I answer with a plea for math-based reality checks.

Science-based Medicine Feed - Tue, 09/03/2024 - 12:39am

Myrna Mattaring, a retired scientist who worked in diagnostic labs, claims that COVID-19 vaccines caused a 1432% increase in cancer cases, a clearly impossible claim. Here I make a plea for examining such claims, including a much more famous and accepted one, with basic math.

The post Quoth Myrna Mantaring: “US government data” confirms a “143,233% increase in cancer cases due to COVID vaccination”? I answer with a plea for math-based reality checks. first appeared on Science-Based Medicine.
Categories: Science

Tuesday: Hili dialogue

Why Evolution is True Feed - Mon, 09/02/2024 - 10:55pm

Meanwhile, in Dobrzyn, Hili can sense the orbit of our planet:

Hili: I suspect that this summer will end.
A: You may be right.

Hili: Podejrzewam, że to lato się skończy.
Ja: Możesz mieć rację.

Categories: Science

Pregnant shark that disappeared may have been eaten by another shark

New Scientist Feed - Mon, 09/02/2024 - 10:15pm
Tracking data from a pregnant porbeagle shark near Bermuda suggest it was eaten by a great white shark – a kind of predation that has never been seen before
Categories: Science

Earthquakes may explain how huge gold nuggets form in quartz rock

New Scientist Feed - Mon, 09/02/2024 - 9:00am
Quartz crystals produce electricity when they are deformed by mechanical stress, which may explain how enormous chunks of gold can form in inert rock
Categories: Science

Lab-grown stem cells could be a 'breakthrough' for cancer treatment

New Scientist Feed - Mon, 09/02/2024 - 9:00am
Stem cells made in the lab may one day aid cancer treatment by reducing our reliance on donors
Categories: Science

We're finally solving the puzzle of how clouds will affect our climate

New Scientist Feed - Mon, 09/02/2024 - 9:00am
Clouds can trap heat or reflect it away from Earth, making their impact on global warming extraordinarily hard to predict. Now, new ways of studying them are lifting the fog
Categories: Science

The best new science fiction books of September 2024

New Scientist Feed - Mon, 09/02/2024 - 8:30am
From Michel Houellebecq to Booker-longlisted Richard Powers and Rachel Kushner, there is plenty of excellent science fiction to read this September
Categories: Science

What are the weird noises coming from Boeing's Starliner capsule?

New Scientist Feed - Mon, 09/02/2024 - 7:33am
NASA is investigating a strange noise coming through the speaker on Boeing’s Starliner capsule, which has been beset with technical issues
Categories: Science

How to avoid being fooled by AI-generated misinformation

New Scientist Feed - Mon, 09/02/2024 - 1:00am
Advances in generative AI mean fake images, videos, audio and bots are now everywhere. But studies have revealed the best ways to tell if something is real
Categories: Science

LLMs: Fighting Fire with Fire

Science-based Medicine Feed - Mon, 09/02/2024 - 12:00am

Using LLM tools to tackle AI-driven science misinformation head-on

The post LLMs: Fighting Fire with Fire first appeared on Science-Based Medicine.
Categories: Science

A Global Color Map of Mars, Courtesy of China’s Tianwen-1 Mission

Universe Today Feed - Sun, 09/01/2024 - 4:37pm

In July 2020, China’s Tianwen-1 mission arrived in orbit around Mars, consisting of six robotic elements: an orbiter, a lander, two deployable cameras, a remote camera, and the Zhurong rover. As the first in a series of interplanetary missions by the China National Space Administration (CNSA), the mission’s purpose is to investigate Mars’s geology and internal structure, characterize its atmosphere, and search for indications of water on Mars. Like the many orbiters, landers, and rovers currently exploring Mars, Tianwen-1 is also searching for possible evidence of life on Mars (past and present).

In the almost 1298 days that the Tianwen-1 mission has explored Mars, its orbiter has acquired countless remote-sensing images of the Martian surface. Thanks to a team of researchers from the Chinese Academy of Sciences (CAS), these images have been combined to create the first high-resolution global color-image map of Mars with spatial resolutions greater than 1 km (0.62 mi). This is currently the highest-resolution map of Mars and could serve as a global base map that will support crewed missions someday.

The team was led by Professor Li Chunlai from the National Astronomical Observatories of China (NOAC) and Professor Zhang Rongqiao from the Lunar Exploration and Space Engineering Center. They were joined by multiple colleagues from the Key Laboratory of Lunar and Deep Space Exploration, the Institute of Optics and Electronics, the University of Chinese Academy of Sciences, and the Shanghai Institute of Technical Physics. The paper detailing their research, “A 76-m per pixel global color image dataset and map of Mars by Tianwen-1,” recently appeared in the journal Science Bulletin.

The optical camera (MoRIC) and imaging spectrometer (MMS) onboard the Tianwen-1 orbiter were used to obtain remote-sensing images of the entire Martian surface. Credit and ©: Science China Press

Several global maps of Mars have been created using remote-sensing images acquired by instruments aboard six previous missions. These include the visual imaging systems of the Mariner 9 probe, the Viking 1 and 2 orbiters, the Mars Orbiter Camera-Wide Angle (MOC-WA) aboard the Mars Global Surveyor (MGS), the Context Camera (CTX) aboard the Mars Reconnaissance Orbiter (MRO), the High-Resolution Stereo Camera (HRSC) of Mars Express (MEX), and the Thermal Emission Imaging System (THEMIS) on the Mars Odyssey orbiter.

However, these maps all had a spatial resolution significantly less than what the CAS team created using images acquired by the Tianwen-1 orbiter. For example, the MGS MOC-WA Atlas Mosaic has a spatial resolution of 232 meters per pixel (280 yards per pixel) in the visible band, and the THEMIS Global Mosaic of the Mars Odyssey mission offers a spatial resolution of approximately 100 m/pixel (~110 ft/pixel) in the infrared band. While the MRO Global CTX Mosaic of Mars covered 99.5% of the Martian surface (88° north to 88° south) in the visible band, it has a spatial resolution of about 5 m/pixel (5.5 yards/pixel).

There has also been a lack of global color images of Mars with spatial resolutions of a hundred meters (110 yards) or higher. In terms of global color images, the Mars Viking Colorized Global Mosaic v1 and v2 have spatial resolutions of approximately 925 m/pixel and 232 m/pixel (~1010 and 255 yards/pixel), respectively. Meanwhile, the MoRIC instrument acquired 14,757 images during the more than 284 orbits executed by the Tianwen-1 orbiter, with spatial resolutions between 57 and 197 m (62 and 215 yards).

During this same time, Tianwen-1’s Mars Mineralogical Spectrometer acquired a total of 325 strips of data in the visible and near-infrared bands, with spatial resolutions varying from 265 to 800 m (290 to 875 yards). The collected images also achieved global coverage of the Martian surface. Using this data, Professor Li Chunlai, Professor Zhang Rongqiao, and their colleagues processed the image data that led to this latest global map of Mars. The team also optimized the original orbit measurement data using bundle adjustment technology.

(a) Level 2C data product as the input, (b) image corrected by atmospheric correction, (c) image corrected by photometric correction, and (d) image corrected after color correction. Credit and ©: Science China Press

By treating Mars as a unified adjustment network, the team was able to reduce the position deviation between individual images to less than 1 pixel and create a “seamless” global mosaic. The true colors of the Martian surface were achieved thanks to data acquired by the MMS, while color correction allowed for global color uniformity. This all culminated with the release of the Tianwen-1 Mars Global Color Orthomosaic 76 m v1, which has a spatial resolution of 76 m (83 yards) and a horizontal accuracy of 68 m (74 yards).

This map is currently the highest-resolution true-color global map of Mars and significantly improves the resolution and color authenticity of previous Mars maps. This map could serve as a geographic reference for other space agencies and partner organizations to map the Martian surface with even greater resolution and detail. It could also be used by space agencies to select sites for future robotic explorers that will continue searching for clues about Mars’ past. It could also come in handy when NASA and China send crewed missions to Mars, which are slated to commence by the early 2030s or 2040s.

Further Reading: Eureka Alert!, Science Bulletin

The post A Global Color Map of Mars, Courtesy of China’s Tianwen-1 Mission appeared first on Universe Today.

Categories: Science

The Road to Singularity: Ben Goertzel on AGI and The Fate of Humanity

Skeptic.com feed - Sun, 09/01/2024 - 3:45pm
https://traffic.libsyn.com/secure/sciencesalon/mss463_Ben_Goertzel_2024_09_01.mp3 Download MP3

Dr. Ben Goertzel is a cross-disciplinary scientist, entrepreneur and author. Born in Brazil to American parents, in 2020 after a long stretch living in Hong Kong he relocated his primary base of operations to a rural island near Seattle. He leads the SingularityNET Foundation, the OpenCog Foundation, and the AGI Society which runs the annual Artificial General Intelligence conference.

Dr. Goertzel also chairs the futurist nonprofit Humanity+, serves as Chief Scientist of AI firms Rejuve, Mindplex, Cogito, and Jam Galaxy, all parts of the SingularityNET ecosystem, and serves as keyboardist and vocalist in the Jam Galaxy Band, the first-ever band led by a humanoid robot.

As Chief Scientist of robotics firm Hanson Robotics, he led the software team behind the Sophia robot; as Chief AI Scientist of Awakening Health he leads the team crafting the mind behind Sophia’s little sister Grace.

Dr. Goertzel’s research work encompasses multiple areas, including artificial general intelligence, natural language processing, cognitive science, machine learning, computational finance, bioinformatics, virtual worlds, gaming, parapsychology, theoretical physics and more. He has published 25+ scientific books, ~150 technical papers, and numerous journalistic articles, and given talks at a vast number of events of all sorts around the globe.

Before entering the software industry Dr. Goertzel obtained his PhD in mathematics from Temple University in 1989 and served as a university faculty in several departments of mathematics, computer science and cognitive science, in the US, Australia and New Zealand. His new book is The Consciousness Explosion: A Mindful Human’s Guide to the Coming Technological and Experiential Singularity.

Shermer and Goertzel discuss:

  • Natural Intelligence and Artificial Intelligence
  • General Intelligence (g) and Artificial General Intelligence (AGI)
  • The alignment problem
  • Consciousness and sentience
  • Zombies and the Hard Problem of Consciousness
  • Data, Sophia, and other robots
  • Altered States of Intelligence
  • Mind uploading and the self
  • How would we know if an AI system was sentient?
  • Can AI systems be conscious?
  • Self-driving cars
  • AI dystopia
  • AI utopia
  • AI protopia
  • UBI
  • What set of values should AI be aligned with, and what legal and ethical status should it have?
  • Can AGI solve political and economic problems?

If you enjoy the podcast, please show your support by making a $5 or $10 monthly donation.

Categories: Critical Thinking, Skeptic

Wearable heart monitor increases diagnosis of irregular heart rhythm

Matter and energy from Science Daily Feed - Sun, 09/01/2024 - 3:18pm
Wearable, long-term continuous heart monitors helped identify 52% more cases of atrial fibrillation compared to usual care, but that did not lead to a reduction in hospitalizations due to stroke, according to a new study.
Categories: Science

Gravitational Wave Observatories Could Detect Primordial Black Holes Speeding Through the Solar System

Universe Today Feed - Sun, 09/01/2024 - 9:34am

Cosmologists have long hypothesized that the conditions of the early universe could have caused the formation of black holes not long after the Big Bang. These ‘primordial black holes’ have a much wider mass range than those that formed in the later universe from the death of stars, with some even condensed to the width of a single atom.

No primordial black holes have yet been observed. If they exist, they might be an explanation for at least some of the ‘dark matter’ in the universe: matter that does not appear to interact with normal matter through electromagnetism, but does affect the gravitational dynamics of galaxies and other objects in the universe.

Now, we might have a new way to detect primordial black holes, although in a severely limited form.

This method comes via gravitational waves.

This illustration shows the merger of two black holes (detected by LIGO on Dec 26, 2016) and the gravitational waves that ripple outward as the black holes spiral toward each other. Credit: LIGO/T. Pyle

First detected in 2015 by the LIGO gravitational wave observatory, gravitational waves are ‘ripples’ in spacetime caused by dramatic events in the universe – most often the collision of giant objects like stellar mass black holes and neutron stars. About 90 confirmed gravitational wave sources have been found by the LIGO-Virgo-KAGRA (LKV) program since 2015.

In a research note published this month, Harvard astrophysicist Avi Loeb examined whether the LKV detectors could catch the signature of primordial black holes – specifically those racing by near the speed of light – or other similar objects moving at high speeds.

“All gravitational wave sources detected sofar involve mergers of stellar-mass astrophysical objects, such as black holes or neutron stars, at cosmological distances,” wrote Loeb in a Medium post in August. But these are not the only possible sources.

“Imagine a relativistic object moving near the speed of light within a distance from LIGO that is comparable to the radius of the Earth. At closest approach, such an object would generate a gravitational signal,” one heavily dependant on its mass and the speed at which it is moving, says Loeb.

With LKV’s current capabilities, the detectors would be able to see any objects moving near to the speed of light with a mass of 100 megatons (the mass of a smallish asteroid several hundred meters across), but only if it came within half the Earth’s diameter of the detectors.

In other words, the LKV detectors would have noticed if an object of this mass passed through the Earth, or very near its surface, in the decade since 2015, if it was traveling at very high speeds.

Of course, if an asteroid of that mass hit Earth at that speed, we’d be well aware of it from the devastating impact. As such, this capability is really of interest particularly for compact objects like primordial black holes, with diameters the size of an atom or smaller, that might pass nearby or even through the Earth without anyone noticing.

No such object has been seen by the LKV detectors.

It is not a surprising result, given that this is a very limited detection capability. It doesn’t tell us about objects further than ~6000 kilometers from Earth’s surface, and also fails to detect slower moving objects.

Future gravitational wave detectors, like ESA’s LISA detector, expected to launch next decade, will expand this range, though not by a lot.

Still, when you are seeking answers to some of the hardest questions in the universe, it’s worth checking where you can. This particular stone hasn’t been left unturned.

Read the Research Note in RNASS here.

The post Gravitational Wave Observatories Could Detect Primordial Black Holes Speeding Through the Solar System appeared first on Universe Today.

Categories: Science

Kruger: Day 1

Why Evolution is True Feed - Sun, 09/01/2024 - 7:15am

I think I’ve already mentioned some things about the giant and fantastic Kruger National Park in NE South Africa, but let’s start with the basics, which means some information and a map from Wikipedia:

Kruger National Park (Tsonga: [ˈkrúːɡà]; Afrikaans: [ˈkry.(j)ər]) is a South African National Park and one of the largest game reserves in Africa. It covers an area of 19,623 km2 (7,576 sq mi) in the provinces of Limpopo and Mpumalanga in northeastern South Africa, and extends 360 km (220 mi) from north to south and 65 km (40 mi) from east to west. The administrative headquarters are in Skukuza. Areas of the park were first protected by the government of the South African Republic in 1898, and it became South Africa’s first national park in 1926.

Here it is below, in red. It’s HUGE! It’s bordered on the east mostly by Mozambique, but we also visited a spot in the north called “Crook’s Corner,” where three countries (South Africa, Mozambique, and Zimbabwe) meet. You can see that spot at the top of the reddish park map below, and it’s where poachers and other criminals used to flee one country to avoid the law by simply stepping across the border (this involves crossing a river) to to one of the other two countries, where they were from from pursuit. Nowadays immigrants from Mozambique cross the river into Kruger seeking a better life in South Africa.

For those who know the park, we entered at the Phalaborwa gate, did a zig-zag heading generally north, often taking dirt roads and taking diversions based on what Isaac heard from his fellow guides and from his own instincts.

We exited the park at the Orpen gate after having stayed four nights in comfortable and inexpensive bungalows: two at Shingwedzi and two at Pafuri. We had about 4.5 days of wildlife watching, at least eight hours a day. I’ll try to reconstruct a map of our travels in the next few days.

Go here to see a good map of the park that includes these locations. If you look at the map, you’ll see that to its west Kruger is surrounded by private game parks and nature reserves. Almost none of these have fences, allowing the animals to transit as they please over a huge area.

But a last meal before I left. A quarter bunny chow in Hoedspruit with beef (the mutton was better but this is still good). It’s filling, cheap, and tasty: a hollowed- out bread bowl (a quarter of a loaf) filled with curry. Note the perfucnctory “salad” to the side.

And the Hoedspruit version of a chocolate milkshake, which was very good:

On to the park. I recommend clicking on the photos to enlarge them.

This is the Phalaborwa gate where you formally enter the park in the north (there are nine entrance gates). You pay by the day on a sliding scale, with South African residents paying about a quarter of what foreigners do, which is fair given the difference in income. The money is for badly needed conservation fees.

Gates are strictly monitored, and open and close at roughly 6 a.m. and 6 p.m. respectively. This is also true of the 12 main “bush camps” where you can stay in well-equipped huts (there are also a couple of fancy private lodges, and “bushveld camps” with fewer facilities). If you are late and the camp is closed, you can still get in (with a reservation), but you have to pay a substantial “fine.”

At the entrance, and throughout the park, there are “sightings boards” showing which charismatic animals have been seen where and when (yesterday or today).  Note that they do NOT post sightings of rhinos because the poachers are, above all, after rhino horns, used in traditional Chinese medicine.

As I mentioned in previous posts. The rangers try to anesthetize all the park’s rhinos and cut off their two horns to prevent the animals from being killed by poachers, but the horns grow back and the process has to be repeated every four years or so.

Our first sighting of animals, apparently a pair of storks. I can’t remember the species.

Our guide Isaac told us that this is a group of social spiders who live in a sac attached to a large, insect-catching web. I believe this is a group of Stegodyphus mimosarum, the African social velvet spider. Individuals in a colony share food and care of the young spiders:

This zoomed-in shot of a raptor with a white chest may be an African hawk-eagle (Aquila spilogaster), but I can’t be sure. Later on we saw and identified a similar-looking species, the booted eagle (Hieraaetus pennatus).

Our first sighting of a mammal that became quite familiar to us, the African bush elephant (Loxodonta africana). (There’s also an African forest elephant in the same genus.) According to a recent census, there are roughly 13,0o0 elephants in Kruger, and the numbers are rising (there were only 725 in 2006).

There is continual debate about whether the increasing population poses a danger to the park, as they knock down trees and displace other species, and for a while they “culled” (i.e., shot) elephants to control the population. Of course big-game hunters in other places shoot them as trophies (an execrable practice), but it’s hard to think about mass killings of these beautiful and highly intelligent creatures when you’ve spent some time watching them.

Here are some small Lala Palms (Hyphaene coriacea). These are small ones, but, as Wikipedia notes,

The spongy pulp of the hard, brown fruit is edible and the fruit is eaten and sold in Madagascar and in eastern Africa; its Swahili name is Mkoma. The flavour has been compared to raisins and raisin bran.

Hippos (Hippopotamus amphibius) are hard to see out of the water, as they prefer spending their days submerged except for their eyes and nose, and generally come out of the water to graze only at night.  (Their skins are very sensitive to sunlight, something you’d think natural selection should remedy.) But on cool days you can see them grazing, always near water.

Here are two. They are considered among the world’s most dangerous animals because they are aggressive, unpredictable, and can run surprisingly fast.  500 people per year are killed by hippos, compared to only 22 for lions, but people are far more scared of lions.

This is a poorly-exposed photo that I included because it’s part of my “animals crossing roads series”.  These are very common antelopes that get no respect because they’re so common in the park: the impala (Aepyceros melampus). They’re everywhere and one tends to overlook them, but they’re very beautiful. Males have horns and females don’t, so these are females.

A larger antelope, the greater kudu (Tragelaphus strepsiceros) with the characteristically spiral horns found only in males. They’re easily identified because both sexes are striped.

Remember, since you’re not allowed to leave your car, all these animals were photographed through open windows in our vehicle. Ergo, most were pretty close to the roadside. Most mammals, save zebras and some antelopes like impala, pretty much ignore cars, although a big bull elephant in the road threatened to charge us after spitting a rare piece of paper at us. Isaac, knowing the signs of elephant aggression (tilting the head sideways is a telling one), backed up the car slowly, and the elephant strode away.

Elephant crossing the road:

A Burchell’s zebra (Equus quagga burchellii) crossing the road. You will see several of these photos in the coming days because it is a ZEBRA CROSSING (in the UK that’s the name for a pedestrian crosswalk).

A rare spot despite its name, here are a few common tsessebe (Damaliscus lunatus lunatus) crossing the road.

A better shot of the tsessebe. In this species both sexes have horns. Horns in males only are a sign of sexual selection, but in some species males have larger horns than females, also indicating sexual selection but likely natural selection as well, giving some reproductive advantage to horned females.

Fun tsessebe facts from Wikipedia:

Several of their behaviors strike scientists as peculiar. One such behavior is the habit of sleeping tsessebe to rest their mouths on the ground with their horns sticking straight up into the air. Male tsessebe has [sic] also been observed standing in parallel ranks with their eyes closed, bobbing their heads back and forth. These habits are peculiar because scientists have yet to find a proper explanation for their purposes or functions

A herd of one of Africa’s most dangerous animals, the African buffalo (Syncerus caffer), a member of the “big five” referred to below; these are animals that are regarded as the most dangerous to hunt and kill with either spear or gun (the other four are lions, rhinos, leopards, and elephants):

One of the “big five” African game, it is known as “the Black Death” or “the widowmaker”, and is widely regarded as a very dangerous animal. African buffaloes are sometimes reported to kill more people in Africa than any other animal, although the same claim is also made of hippopotamuses and crocodiles. These numbers may be somewhat overestimated; for example, in the country of Mozambique, attacks, especially fatal ones, were much less frequent on humans than those by hippos, and especially, Nile crocodiles. In Uganda, on the other hand, large herbivores were found to attack more people on average than lions or leopards and have a higher rate of inflicting fatalities during attacks than the predators (the African buffalo, in particular, killing humans in 49.5% of attacks on them), but hippos and even elephants may still kill more people per annum than buffaloes. African buffaloes are notorious among big-game hunters as very dangerous animals, with wounded animals reported to ambush and attack pursuers.

In male buffalo, the horns grow together, fusing in the middle of the head in a structure known as a “boss.” This one doesn’t have a boss:

Here’s a “boss” male with the fused horns, as well as an oxpecker nibbling at his nose.

Below: the most iconic tree in Africa, the Baobab (Adansonia digitata). I didn’t see it leafed out (that’s during the African summer), but it’s unmistakable because of its large, bulbous trunk (It’s actually classified not as a tree but a succulent.) There are 8 species, but only this one is endemic to mainland Africa (6 others are native to Madagascar and one to Australia.

They can get very old (carbon dating puts an age limit of about 2,000 years). The tree has many uses for man, beast, and bird. Young leaves can be stewed as a vegetable, the roots and fruits are edible, and the seeds can be made into a flour. The bark can be made into fiber and clothes, and, in times of drought, elephants eat the water-rich underbark. And as for birds, see the second photo below.

There are often signs under baobabs in the park, and here’s one of them. What kind of miscreant would throw stones at owl holes?

The lovely impala lily (Adenium multiflorum), native to eastern and southern Africa. It’s a small succulent tree and was blooming everywhere in the dry winter season of our visit. The flowers are gorgeous and trees are planted widely around the camps.

Another baobab. I’d love to see these in the wet summer.

Isaac, the crack spotter, suddenly asked me out of nowhere, “Would you like to see a giraffe lying down?” I said, “Sure,” and asked him if this was an unusual event. He said “yes”.  Sure enough, Isaac had spotted two of them far before I could see them:

You may have wondered if giraffes sleep. The answer is, “Yes, but not much,” probably because they have to keep alert for predators (they can be taken down by lions, leopards, hyenas, and wild dogs, all of whom first go for the legs). Here’s some info about giraffe sleep from one website:

To start, let’s clarify that giraffes only sleep a few hours a day.

Some giraffes don’t even sleep that much. In captivity, adult giraffes have been observed sleeping as much as four and a half hours a day. In the wild, giraffes might only sleep about 40 minutes a day—and only about three to five minutes at a time.

Researches have observed three types of sleep in giraffes: standing, recumbent, and paradoxical. The latter sleep type is similar to REM (rapid eye movement) sleep. Standing sleep is characterized by a giraffe standing up, yet motionless, with its head tilted slightly more forward than it is when awake. This is thought to be essentially a light nap for giraffes and makes up a majority of their sleep.

During recumbent and paradoxical sleep, a giraffe can be observed lying down with their legs folded under them, their neck turned and arched backward and their heads resting on their rumps or the ground—similar to a swan.

When they drink at a waterhole, giraffe splay their legs widely to lower their body, allowing that long neck to reach the water.

A non-napping giraffe:

Zebra crossing!

We crossed the Tropic of Capricorn, where it’s allowed to leave the vehicle. I love official lines like the Equator (which I’ve also straddled) and borders between countries.

The Tropic of Capricorn is explained in the second photo below: it’s the furthest latitude south where the Sun appears directly overhead. That event occurs around December 21, the Winter Solstice in the northern hemisphere. Wikipedia notes that this is “the dividing line between the Southern Temperate Zone to the south and the Tropics to the north.”

Of course I had to straddle it: the line of rocks running between my legs.  Now I can say that I’ve stood astride this line, as well as the Equator. (I can’t remember standing on the Tropic of Cancer; the closest place to Chicago would be in Mexico.)

The explanation:

Two more giraffes. I couldn’t get enough of these majestic and beautiful animals. They’ve evolved, of course, to access leaves high up on trees that other animals can’t reach: an adaptation that comes with several costs.  They give birth standing up and the babies have a long tumble to the ground, which animates them to start their lives.

Here’s a giraffe giving birth in the wild. The baby takes its first wobbly steps within only a few minutes:

I believe I’ve discussed before the phenomenon of “dagga boys”: African buffalo who have been expelled from their herd because they’re old and can’t hold a position in the hierarchy (ca. ten years). They must thus wander, solitary or with a couple of other dagga boys, until they die or are taken down by predators like lions. They often roll in the mud because they have skin conditions, and are especially dangerous because, lacking the defense of their herd, they’re prone to attack.

In a later installment we’ll see the remains of a dagga boy killed by lions. These solitary animals, I think, must be lonely, and I find them ineffably sad. But such is nature.

A lovely male of the Greater Kudu.

And a giraffe sticking out its tongue:

One of the most amazing things we saw on day 1 (and remember, this is only the first of five days) was a huge herd of elephant digging for water in a dry river bed. Apparently elephants have a way of detecting water close to the surface, and when they find it, and are thirsty, they use their legs, tusks, and trunk to excavate a well that can be more than a meter deep. Here’s one female digging for water, and she found it:

This is only a small number of the more than fifty elephants I counted in the vicinity, and they’re all either digging for water or trying to get water from holes dug by others. Naturally the diggers wants a monopoly on their water and try to drive interlopers away, except for mothers who allow their babies to drink with them.  An elephant can take in 100 liters at a time, and about 240 liters per day.

Two photos of a mom allowing her baby to drink:

A bit more than half the group (I couldn’t get them all in one photo):

Finally, a male giving us the stink eye. Notice also that there are impala, kudu, and a single Marabou Stork  (Leptoptilos crumenifer) to the right of the elephant.

That was just Day One. There’s lots to come, but we made camp before closing time and had dinner (there are small and inexpensive restaurants in the camps).

More when I get time, probably tomorrow.

Categories: Science

Sunday: Hili dialogue

Why Evolution is True Feed - Sun, 09/01/2024 - 12:31am

Meanwhile, in Dobrzyn, Szaron gives Hili an enigmatic reply:

Hili: Are you thinking?
Szaron: No, I’m still asleep.

Hili: Czy myślisz?
Szaron: Nie, nadal śpię.

Categories: Science

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