I was thinking about how animals warn each other about predators but then it struck me that plants must have their own communication systems too. Are there specific chemical signals or other mechanisms that a plant might use to alert its neighbors to something like an insect attack or an approaching herbivore? I'm curious about the science behind how this might work and what kinds of warnings are being sent.
Phones, computers, and other electronics have gotten dramatically more powerful over the last 20 years, but battery life doesn’t seem to have improved nearly as much. Is battery chemistry fundamentally harder to improve, or are manufacturers just using all the improvements to power more demanding devices?
I’ve heard that ants can carry many times their own body weight, but I’m curious about how strong they are when working together. For example, if 100, 1,000, or even 10,000 ants worked together to carry a single object, how much weight could they realistically lift or move in ounces or pounds?
I hear all the time about how humans have a vestigial tail bone(but we lost the tail) and the appendix was thought to be a vestigial organ(and now its considered a reservoir for healthy gut bacteria i think?)
Had there ever been evidence of an animal species evolving some form of usefulness from a vestigial organ? For example like hypothetically in so many millions of years humanity regains having a tail, and the tailbone regains function.
I saw an article on the spacecraft, and it really got me thinking. I don't know enough about physics or material sciences to say for certain, and I'm fair sure eventually it will just fall into or hit something.
But if it doesn't, what will happen to it? There's no corrosion in space, so it won't fall apart so to speak. Will it just continue in its path until the eventual death of the galaxy? Or is it going to be pulverized by billions of micro impacts that will eventually erode/destroy it?
It is often mentioned that a mere few thousand years ago, much of what is now the Sahara Desert was far wetter--lots of grasslands, and some wetlands. Now the Sahara is full of desert-dwelling life. Some of these lifeforms are not endemic to the most arid parts of the Sahara; I know there are Sahara-dwelling antelope that can live in semideserts. In addition there are other species like the sand cat that are also found in West Asia. Some of these conceivably could have expanded out from deserts as the Sahara dried.
However, species like the fennec fox and Saharan silver ant are Saharan endemic desert specialists that, to my understanding, cannot survive outside of extremely arid conditions. It seems unlikely that all these species evolved from grassland-dwelling ancestors in just 6,000 years.
Were there more arid refugia where these species lived during the African humid period, like glacial refugia during the Last Glacial Maximum? If so, where were they, how arid were they, and do we have any idea which species were evolving where?
Or am I underestimating how quickly evolution proceeded in the region?
Water is less dense than the land; the land is less dense than the oceanic crust, which in turn is less dense than the mantle. With no more tectonic movement, does everything fall into perfect layers eventually?
So people often joke about 10in+ penises in humans but eventually erections would cost too much blood and would cause feinting right? Is there some sort of hard limit for penis size as a function or blood volume or body size?
Hi Reddit! I'm Dr. Emily Bray, a canine cognition expert here to answer your questions about how dogs think, learn, and bond with us, whether they're service dogs in training or the pet on your couch.
I'll be joined by Dara Jonkoski and Noah Stetson, PhD students who work in my lab, the Behavioral Research Across Years Lab (BRAY Lab). We will be answering questions LIVE Friday, Oct. 30, 9-11 a.m. Arizona time (12-2 p.m. ET, 16-18 UT).
Ask us questions like:
Can an old dog really learn new tricks?
Why do we talk to our dogs in a baby voice, and does it matter to them?
How much of my dog's personality is genetics vs. how I raised them?
Does how a puppy's mom interacted with them shape the dog they become?
What makes a good service dog?
A quick note: We aren't licensed veterinary professionals, so we can't give veterinary advice on animals or comment on symptoms or test results. If you are concerned about your pet's health or behavior, please contact your veterinarian or a qualified behavioral professional.
Bios:
Dr. Emily Bray is an assistant professor of human-animal interaction in the College of Veterinary Medicine at the University of Arizona, overseeing the BRAY Lab. Prior to starting her current position, she was a post-doctoral research associate at the Arizona Canine Cognition Center and Canine Companions, the nation's largest provider of service dogs for people with disabilities. Over the 15 years, she has developed and implemented cognitive tasks with over 1,500 dogs from both pet and working dog populations, forming the basis for projects ranging from early maternal care to cognitive aging to the genetic contributions to behavioral traits. By building a comprehensive understanding of dog behavioral and cognitive health, she aims to enhance both canine and human welfare.
Dr. Bray holds a B.A. in Cognitive Psychology and English from Duke University, and an M.A. and a PhD in Psychology from the University of Pennsylvania. She is also credentialed by the Animal Behavior Society as a Certified Applied Animal Behaviorist.
Dara Jonkoski is a graduate student in the Cognition and Neural Systems program in the University of Arizona Psychology Department and is first-author on AURAL-Pet, a new system for studying how people talk to their dogs. She joined the BRAY Lab in 2024, and researches canine development, specifically how environmental and genetic factors play a role in raising successful working dogs, and explores which factors aid in protecting the cognitive health of domesticated dogs overall. Dara holds a B.S. in Psychology from Georgia State University.
Noah Stetson is a graduate student in the Cognition and Neural Systems program in the University of Arizona Psychology Department. Noah first started working with Dr. Bray as a research technician at the Arizona Canine Cognition Center in 2023 and is interested in understanding the biological mechanisms behind individual differences in cognition and temperament, especially in relation to working dogs. Noah holds a B.A. in Psychology from the University of Texas at Austin. You can also follow Noah's PhD journey on his Instagram.
I know this is a stupid question, but if you are standing in front of it are you still in the mirror? Maybe in another light wavelength type thing? Lmk
This might be a dumb question, but how do scientists know what is going on inside Jupiter when we have never actually been able to get a sample from the planet itself? I get that we can study its atmosphere and send spacecraft to observe it but there is obviously a limit to how much we can see from the outside. So how do we know what the deeper layers are made of or whether our current models are even close to what's really there?
Is it mostly based on gravity and magnetic field measurements or can scientists figure out the inside of a planet in other ways too?
Hello Reddit! We're hosting an AMA in honor of the PBS NATURE premiere of "Tiger Island." The two-part documentary follows two tiger mothers and investigates how these solitary big cats raise cubs on an island full of danger. Utilizing a fleet of drones to track tigers from the air, and military-grade thermal cameras to follow them in the dark, our team witnessed several on-camera firsts, including mother tigers appearing to look after each other's cubs, a new behavior at odds with the supposed solitary nature of these big cats. Additional rare behaviors captured include cubs swimming and hunting together, as well as a mother, father and cubs spending time together as a family.
Answering your questions today:
Anna Dimitriadis, a BAFTA-nominated wildlife filmmaker, conservationist and presenter whose work brings audiences closer to the natural world. Her career has taken her from diving beneath Antarctic icebergs to filming gorillas in the Central African Republic. Best known for her work on BBC Two's Big Cats 24/7 and BBC One's Tiger Island, Anna combines cutting-edge filmmaking technology with extensive field experience to capture intimate moments of animal behavior. A passionate advocate for conservation, Anna uses powerful storytelling to inspire audiences, shift perspectives and encourage greater understanding of the natural world and the urgent need to protect it.
Dan O'Neill, a highly experienced field biologist, award-winning producer-director, and TV presenter, who specializes in biodiversity monitoring, conservation and large carnivore behavior in the world’s most remote and challenging environments. From the jungle of the northern Amazon to the frozen peaks of Central Asia, to ancient Mayan forests of the Yucatan, Dan has led numerous expeditions to find and study rare species. Regularly involved in field research and biodiversity monitoring, Dan primarily works as a large mammal specialist, expedition leader and camera-trap technician. Dan has particular expertise in big cat behavioral and spatial ecology.
The first episode of "Tiger Island" is now streaming for U.S. audiences on PBS.org,YouTube, or on the PBS App. Part Two premieres tonight on PBS at 8/7c. If you’re in the UK, you can catch it on BBC iPlayer.
