Tay (Antonio J. Osuna Mascaró)

19 Jan

Cow Tools! We have lived alongside cows for nearly 10,000 years. We breed them and exploit them It is now, only now, that we have discovered THEY CAN USE TOOLS Here I describe our study (paper) www.sciencedirect.com/science/arti... in @currentbiology.bsky.social with @auersperga.bsky.social

Invisible Extinction Thousands of Egyptian vultures may conceal a much smaller genetic population. In this study, they surveyed approximately 3000 birds and estimated that they have an effective population size (genetic diversity) of only 9 individuals (paper) link.springer.com/article/10.1...

1/9 Birds make ultrafast decisions In this study, carrion crows were able to make decisions twice as fast as primates, including humans. Let me briefly explain the findings and share my thoughts. (paper) www.science.org/doi/10.1126/...

8/9 When rodents are asked to make similar decisions based on visual stimuli, they are relatively slow. But when the stimuli are olfactory, they can make decisions in just 223–229 ms!!! (paper, 2003) www.nature.com/articles/nn1... DOI 10.1038/nn1142

9/9 Crows really are extraordinarily fast at making visual decisions, but I think it's important to consider a species' ecology when interpreting these results. I also suspect we'll find similarly fast decision-making in many other bird species.

6/9 There may be several, non-mutually exclusive reasons why they make decisions so quickly. Birds have exceptionally high temporal visual resolution (up to 140 Hz), but their neurons are also packed closely together, and flight imposes strong evolutionary pressures for rapid processing.

7/9 Personally, I find this an astonishing result, another in a long series of remarkable findings in birds, particularly crows, and from these researchers. But I don't think we should assume that this is some kind of superpower beyond the reach of mammals.

4/9 The bird would then initiate a movement to indicate its choice. And here's the remarkable part: the crows took only about 235 milliseconds to reach this point! Comparable experiments with primates, including humans, have reported reaction times ranging from 410 to 820 ms.

5/9 That's extraordinarily fast. They took slightly longer when decisions were more difficult (suggesting genuine decision-making rather than an automatic response), and their accuracy depended on task difficulty: 99% correct at 81% coherence, compared with 57% at 3%.

2/9 Two crows watched a cloud of moving dots on a screen and had to determine the predominant direction of movement (four possible directions). There were several difficulty levels, ranging from impossible (completely random motion) to 3%, 9%, 27%, and 81% motion coherence.

3/9 While they performed the task, the authors recorded the activity of 248 neurons in the nidopallium caudolaterale (the avian functional equivalent of the prefrontal cortex). These neurons progressively increased their activity as sensory evidence accumulated, until a decision was made!

1/3 Honey bees steal pollen from other bee species. They do this much more frequently than previously thought. The authors speculate that this behavior may depend on pollen availability and individual experience. (paper) link.springer.com/article/10.1...

2/3 They steal pollen from species such as bumblebees and carpenter bees, removing it directly from their bodies. Sometimes (but not always), the other bees try to shake them off and fly away, but the honey bees may pursue them.

3/3 The authors speculate that there may be some degree of individual specialization. Some honey bees may learn that they can obtain pollen from other species and exploit this resource, even when pollen is available from flowers. It was conducted in two French national parks; 15% did it.

1/4 Human hunters do not replace apex predators Hunting and natural predation do not have equivalent ecological effects. Apex predators are associated with diverse and robust animal communities; hunting is associated with the opposite. (paper) besjournals.onlinelibrary.wiley.com/doi/10.1111/...

3/4 How animals perceive humans is also crucial. Animals respond very differently to our species than to natural apex predators. In general, they avoid us much more intensely. Following human presence, they typically take much longer to return to the same location.

4/4 In areas with natural apex predators, animals are more evenly distributed. In contrast, in areas frequented by human hunters, many species become concentrated in places with less human activity. This makes populations more vulnerable and increases their risk of local extinction.

2/4 There are many reasons for this. Humans are very different predators, with ecologically catastrophic impacts: we exploit a wide range of species, use technologies that leave prey with little chance to defend themselves, target large adults, and our survival does not depend on the prey we hunt...

youtube.comDream of birds: the lost songs of Argentina | Ornithology DocumentaryWhat happens when a forest loses its birdsong? Subscribe to The Guardian on YouTube ► https://www.youtube.com/user/theguardian?sub_confirmation=1 Following clues hidden in the sounds birds make…

Dream of Birds A wonderful documentary (14 minutes) about Gabriel Mindlin’s research (in Spanish with English subtitles). From the study of birds’ dreams to how this led them to combat the cultural extinction of birdsong www.youtube.com/watch?v=PfVr...

1/7 Spiders are not robots Researchers investigated the ability of cellar spiders (Pholcus phalangioides) to flexibly adapt when multiple prey items land in their webs, before they can escape. The authors explain their findings in terms of insight (paper) link.springer.com/article/10.1...

6/7 In my opinion, this is far from demonstrating insight in spiders, nor does it need to do so to be important or surprising. Insight, the ability to suddenly arrive at a solution to a problem, is not a way of finding solutions without learning. Quite the opposite.

7/7 What this study does demonstrate is the remarkable behavioral flexibility of these spiders, which are so common in European cities. And that is more than enough. P.S. Here are some photos of one of the spiders I've shared my apartment with in Vienna. I find her maternal behavior fascinating : )

4/7 What the researchers discovered is that spiders switch between these strategies very flexibly, depending on the situation. These strategies do not appear to depend on learning (previous solutions did not predict subsequent ones, performance did not improve over the course of the experiment, etc)

5/7 Because the spiders used different strategies, individuals switched methods between trials, and there was no evidence of improvement through trial and error, the authors argue that these findings are more consistent with insight than with other cognitive processes.

2/7 The spiders were presented with either a single fly (control), three flies simultaneously, or three flies arriving at short intervals. The spiders used three different strategies to handle the flies before they could escape:

3/7 a) They immobilized the flies where they had landed. b) They captured each fly individually but brought them together before feeding (sometimes holding one while eating another). c) They wrapped two flies together into a bundle that they carried with them.

Great apes anticipate others' surprise when their expectations are about to be violated. To do so, they integrate: what the other individual believes they will find, what they will find, and the discrepancy between both (!) (preprint) www.biorxiv.org/content/10.6... by @isabellelaumer.bsky.social

Ants have a complex memory In this experiment with M. brevinoda, they demonstrate that it can be modified, that those changes can be reversed, and -particularly interesting- that they exhibit latent learning (without any need for reinforcement) (paper) link.springer.com/article/10.1...

Possible social medication in bumblebees. In this study, bumblebees exposed to a fungus that affects larvae progressively increased their preference for artificial nectar containing quercetin (a vegetable antioxidant with antimicrobial properties) (paper) royalsocietypublishing.org/rsos/article...

1/7 Anesthesia across phylogeny From nematodes to humans, anesthesia induces remarkably similar changes in neural activity. And this could provide important clues about the neural foundations of consciousness. (paper) www.nature.com/articles/s41...

6/7 What is particularly surprising is that anesthetics acting through different molecular mechanisms produce such similar changes in neural activity. This suggests that different pharmacological pathways can lead to a common functional state of the nervous system.

7/7 None of this demonstrates that C. elegans is conscious. But perhaps some of the neural dynamical properties that contribute to making consciousness possible in more complex species have very ancient evolutionary roots.

4/7 Synchronization between brain regions also decreases. Their activity becomes less coordinated, probably compromising the integration of information. The authors describe this combined effect as the "spatiotemporal isolation" of neural activity.

5/7 Interestingly, in two macaques anesthetized with propofol, electrical stimulation of the centromedian thalamus reversed some of these changes and restored behavioral responsiveness. And this happened while the animals were still receiving the anesthetic (!)

2/7 The researchers studied six species: humans, macaques, marmosets, mice, zebrafish, and C. elegans. Despite their differences and the use of anesthetics with distinct mechanisms of action, they identified 485 features of neural activity that changed consistently.

3/7 One of these changes involves a loss of temporal continuity in neural activity: under anesthesia, activity in a given region becomes less dependent on its own previous activity. In other words, information appears to persist for less time in ongoing neural activity.

Supercompetitors Deer seem to fear wild pigs more than coyotes Hearing wild pigs nearby makes white-tailed deer more likely to flee (81% of females, 74% of males) than hearing their own predators (64% and 42%) (paper) www.nature.com/articles/s41...

pioneerworks.orgThe Dreams of Octopus and Cuttlefish | BroadcastHow the skin reveals a world within.

Octopus dreams A fantastic piece by Peter Godfrey-Smith, in the form of a review, about the evidence of dreams in cephalopods, their possible convergent evolution, and even the possibility of states similar to daydreaming, as we have them. (blog) pioneerworks.org/broadcast/ce...

Tay (Antonio J. Osuna Mascaró) reposted

Naukas.com

@naukas.bsky.social

No sé si lo sabéis pero... Este sábado 10 de octubre tendremos un evento en SEVILLA!! Estaremos en el Teatro Central fusionando Arte, música, arquitectura, pintura y cine con ciencia en el NAUKAS SEVILLA FUSIÓN!! Un evento Naukas en Andalucía!! No os lo podéis perder naukas.com/2026/10/05/e...

naukas.comEste sábado 10 de octubre nos vemos en el Teatro Central para el evento Naukas Sevilla FUSIÓN Ciencia y Arte - NaukasDesde hace muchos años nos habéis estado pidiendo un evento en el sur… y ahora lo tenemos. Os presentamos NAUKAS SEVILLA FUSIÓN 2026, un espectáculo científico artístico que reunirá a divulgadores, in...

sciencedirect.comhttps://www.sciencedirect.com/science/article/pii/S0168010226001045

1/7 Psilocybin and Alzheimer’s in rats A single tolerated dose of psilocybin reversed spatial memory-related impairments in a rat model of Alzheimer’s. (paper) www.sciencedirect.com/science/arti...

6/7 Both the dangerous hyperthermia and the recovery of functions through new neural circuits strongly recall the case I recently discussed in another thread: an elderly woman who recovered several functions after a deep sleep-like state, also with suspected hyperthermia.

bsky.appTay (Antonio J. Osuna Mascaró) (@biotay.bsky.social)1/8 Psilocybin and Alzheimer’s A clinical case of a woman in her 80s with advanced Alzheimer’s disease who was given 5 g (a so-called “heroic dose”) of Psilocybe cubensis mushrooms, Enigma strain,…

7/7 bsky.app/profile/biot...

sciencedirect.comhttps://www.sciencedirect.com/science/article/pii/S0168010226001045

4/7 It is also interesting that, although the rats recovered from their memory impairments, the authors did not find a clear electrophysiological signature distinguishing them from rats that had not received psilocybin.

5/7 The authors suggest that the recovery of normal behavior despite the lack of electrophysiological evidence may be due to increased structural plasticity: new connections that restore functions without restoring the damaged circuits themselves.

sciencedirect.comhttps://www.sciencedirect.com/science/article/pii/S0168010226001045

2/7 There are some important caveats before anyone thinks this is a solution to the disease. These were ICV-STZ rats and, although this model is used to study Alzheimer’s-like pathology, it does not fully reproduce human Alzheimer’s disease. (This is a horribly invasive study)

3/7 Also, at the tolerated dose, the rats performed almost like control animals in some memory tasks. But at intermediate and high doses, the animals did not survive (hyperthermia). Brains altered in this way may tolerate the serotonergic challenge posed by psilocybin poorly.

We are fish This is a good reminder that "fish" is an artificial term with practical use, but no actual cladistic validity. After all, humans should be classified as fish, too.

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Stealing Among Friends (Chimpanzees) In this experiment, chimpanzees stole food slightly less from their friends (61% vs 70% of the time). It is also interesting that they got angrier when a friend stole from them, but their anger subsided more quickly (paper) www.sciencedirect.com/science/arti...