Showing posts with label elephants. Show all posts
Showing posts with label elephants. Show all posts

Tuesday, April 2, 2019

5 Animal Species With Surprising Memories

A repost of an original article from The Scorpion and the Frog.

We often think of animals as having hilariously short memories – the “memory of a goldfish”, if you will. But many animals have memories that can put yours to shame.

There are many different kinds of memory and each of them is controlled differently by different parts of the brain. Short-term memory can be thought of as the brain’s scratch pad: It holds a small amount of information for a short period of time while your brain decides whether it is worth retaining in long-term memory or if it can just fade away. When a short-term memory becomes a long-term memory, this process is called consolidation and involves physiological changes in the brain.

Long-term memory can be further divided into two main types: procedural memory and declarative memory. Procedural memory is used to remember how to do things and what objects are needed to do those things. Declarative memory is used for recall and can be further divided into memory used to recall facts (semantic memory) and events (episodic memory).Each of these different types of memories are stored in different parts of the brain. Furthermore, different types of facts (remembering faces versus numbers, for example) and different types of events (depending on if they have an emotional component or not, for example) are also stored in the brain differently. Because species differ in how we rely on our brains, it makes sense that this might be reflected in our abilities to remember in different ways.

So let’s check out some of the most amazing memories in the animal kingdom:

Do you know what all your kids and nieces and nephews are
doing right now? These elephants do. Photo by PJ KAPDostie
at Wikimedia.
1) They say an elephant never forgets. Elephants are very social animals that live in large stable herds. This has led to some incredible feats of social memory. They can keep track of the whereabouts of 30 group members at once and they can remember an animal they briefly met over 20 years ago. For an animal that lives about 50 or 60 years, this is very impressive. Elephants also have outstanding episodic memory: In 1993, Tarangire National Park in Tanzania suffered the worst drought that it had seen in 35 years. It was so severe that it killed 20% of elephant calves, compared to the average loss of about 2%. Of three herds that lived in the park in 1993, two of them were led by females that had lived during the severe droughts of 1958-61 and those herds left the park and were more successful at finding food and water. The herd that stayed was led by a younger female that had never experienced such a severe drought and that herd suffered 63% of the total mortality.

Dolphins never forget a name. Photo from the
NOAA Photo Library available at Wikimedia.
2) Bottlenose dolphins have even more incredible social memories. They, like elephants, live in complex social groups. Each dolphin has a unique whistle that it uses like a name. When they are played recordings of whistles of companions they lived with years or even decades earlier, they approach the speakers for longer than when they are played the whistles of dolphins they never met. The fact that they, like elephants, remember companions for over 20 years is much more impressive because their lifespan is only 40-50 years!

Sea lions can remember
meaningless tricks for years.
Photo by LSA2886 at Wikimedia.
3) Sea lions have amazing procedural memory. In 1991, marine biologists at the University of California, Santa Cruz, taught a California sea lion named Rio a card trick. They held up one card with a letter or number on it and another set of two cards: one that matched the first card and one that did not. Rio learned to pick the matching card to be rewarded with a fish. Everyone was impressed and she didn't do the trick again... until 10 years later, when researchers pulled out the cards and asked her to do it again. Rio had the same score in 2001 with no practice that she did in 1991 when she originally learned the trick!







Clark's nutcrackers can remember where they stashed
30,000 pine nuts.I can't even keep track of my keys.
Photo by Gunnsteinn Jonsson at Wikimedia.
4) Clark’s nutcrackers can remember the exact location of 30,000 pine nuts. This kind of superhero ability is born out of necessity: nutcrackers completely rely on their caches of food to get them through the winter. However, despite their amazing long-term spatial memory, their short-term memory is below average: they can’t even remember the color of a light for 30 seconds.

5) Chimpanzees can put your working memory to shame. Working memory is a form of short-term memory that is applied to a task. A group of researchers taught chimpanzees to do a task in which they were shown the numbers from 1-9 in random locations on a computer screen. When the numbers are covered, chimps can remember where each number was. Furthermore, they only need to see these randomly placed number for a few seconds to get this task correct. In comparison, only people that are considered savants have comparable abilities.



Monday, July 31, 2017

How Some Unique Animals Beat the Heat

Man, is it hot out there! While I tuck away in my cool, air-conditioned office, I think about those incredible animals that beat the heat with their own bodies and strategies. It turns out, there are only four major ways to exchange heat with your environment: conduction, convection, radiation and evaporation. The animals that are best equipped for a hot summer are those that take creative advantage of these mechanisms of heat transfer.

"My, what big ears you have!"
"The better to thermoregulate with, my dear!"
Photo by Bernard DUPONT at Wikimedia Commons.
We all exchange heat with our environment wherever our body comes in contact with the environment, namely, across our skin. Animals can increase the rate of this heat-exchange by having a larger surface area relative to the volume of their heat-containing bodies. Big, round animals have a particularly hard time dispersing excess heat, because they have a lot of heat stored in their big bodies, and proportionally not much surface area for the heat to leave from. You may think elephants have such big ears for hearing, but the truth is that they are major temperature-regulation organs. Big, flat body structures provide that added surface area for excess heat to dissipate from. Elephants have large ears with lots of large blood vessels, so they can pump hot blood from the body out to the ears, where they are closer to the cooler environment to dissipate by conduction and convection. The cooler blood then returns to the body core to cool it down.

Built for a life in the cool underground.
Photo by Ted M Townsend at Wikimedia Commons.
Reptiles use a different approach to take advantage of principles of conduction and convection, by burrowing. Burrows create a layer of insulation (usually soil and plant matter) that slows heat exchange and keeps the area below ground a more constant temperature. This means that, compared to the outside, burrows remain cooler in the summer and warmer in the winter. Many reptiles go into their summer burrow in the heat of day and emerge during cooler times of day. Blind lizards, however, take this burrowing idea to an extreme. Blind lizards are a family of legless lizards found in tropical forests. They are small, skinny, and have narrow heads, which make them look more like an earthworm than a lizard, but it also gives them great burrowing efficiency to stay underground and avoid the heat.

A dragonfly exposing as little of his body to the sun
as possible. Photo by Raphael Carter at Wikimedia Commons.
On a hot summer day, we all seek out the shade. This is to reduce the heat we absorb through radiation, and most of this radiation comes from the sun. But what do you do if you can’t find shade? Some dragonflies and damselflies raise their abdomens to aim their rear-ends towards the sun so they can shield themselves from the full-on intensity of the sun’s rays. This body position is called the obelisk posture, because when the sun is directly overhead, the insect’s handstand looks like an obelisk.

Really? Crapping on my own feet?
There has GOT to be a better way.
Photo by Rob Schoenmaker at Wikimedia Commons.
Evaporation is the most efficient way to dissipate heat. Some animals swim, some animals sweat, some animals pant, but vultures and storks win the cooling efficiency award. Vultures and storks. . . poop on their own legs and feet. With this approach, called urohydrosis, the animal releases a mixture of urine and poop through their single excretory hole, called a cloaca, onto their legs and feet. The subsequent evaporation from the high surface area of their long legs helps them to cool off.

So what can we learn from these heat-beating experts (without pooping on ourselves)? If you are hot, spread your body out, stay in the shade, and wet an area of your body with high surface area and exposed blood vessels (namely, your inner wrists and forearms). I’d use water though.

Tuesday, May 9, 2017

The Best Moms in the Animal Kingdom

Moms are really important to life on Earth, as evidenced by the fact that maternal care is fairly common across the animal kingdom. In most species, females produce fewer, larger, and costlier eggs than males do sperm. Therefore, it is usually beneficial to females to maximize the possible success of each one, sometimes by gestating them inside their own bodies (as mammals do), or incubating the eggs until they are ready to hatch (as birds do), or by providing prolonged protection, food and training until they are ready to take on the world for themselves. But there is still a lot of variation in how and how much each mother gives to her offspring. Here are some of the best moms in the animal kingdom:

1. The Endurance Prize goes to orangutans: Orangutan infants cling to their moms’ bellies non-stop for the first four months of their life and they continue to completely depend on their moms for the first two years for food and transport. Their moms will continue to carry them often until they are five and will sometimes continue to breastfeed them until they are eight! After that, the young still stay close to mom, learning from her and helping her until they are sometimes in their teens.

An orangutan mama and toddler. Photo by Mistvan at Wikimedia Commons.

2. The Provider Prize goes to the crab spider, Diaea ergandros: These crab spider moms create a brood chamber and nest out of eucalyptus leaves. They guard their eggs and then spiderlings, providing protection and prey for food. These moms also make extra eggs, just for their babies to eat, and finally, they give themselves… quite literally! The babies eat their mothers completely in a rare behavior called matriphagy.


3. The Pregnancy Prize goes to elephants: Elephants are pregnant for about 22 months… nearly two years! And a baby elephant is not light to carry around… by the time it is born, it will weigh nearly 250 pounds! Just the thought of it makes me uncomfortable. So why would elephant moms need to gestate their young for such an incredibly long time? It is thought that the long gestation is needed for the proper development of their brains, so they are born with the complex cognitive and social skills needed to survive in their herd.

An African elephant family plays in the hot sun. Photo by Bernard Dupont at Wikimedia Commons.

4. The Brooding Prize goes to a deep-sea octopus: Two years is a very long time to carry a developing baby inside your body, but some animals care for their developing empryos ouside of their bodies with a behavior called brooding. Although brooding may sound easier than pregnancy, it is not for the faint of heart. A deep-sea octopus was observed brooding her eggs in the Monterey Submarine Canyon off central California for 53 months… That is nearly 4 and a half years! And that whole time she did not eat, but instead guarded and aerated the water around her precious eggs.

A deep-sea octopus. Photo by NOAA at Wikimedia Commons.

5. The Multi-Generational Prize goes to humans: Many human moms are not only good mothers, but also good grandmothers. Grandparenting is extremely rare in the animal kingdom (the first documented case of grandparenting in non-humans was as recent as 2008) and human females excel at it. They provide care, advice, resources, lessons and hugs to increase the success of their offspring and grand-offspring… It’s amazing other species haven’t picked up on this amazing secret yet!

The best moms in the animal kingdom. Photos by Sarah Jane Alger.

Tuesday, March 7, 2017

Caught in My Web: Perplexing Animal Behaviors

Image by Luc Viatour at Wikimedia Commons.
Sometimes animals behave in such an odd manner, that even the animal behaviorists aren't sure what the heck they are doing or why. So for this edition of Caught in My Web, we just wonder.

1. Last month, a dog was hit and killed by a car. His fellow doggy-companion then used his nose to bury him. Was this a funeral? Is this just canine burying behavior? We don't know, but it's been seen before. This video is from 2013:



And here is another from 2015:


2. Have you seen this video of turkeys circling a dead cat?

3. An African elephant approaches a white rhino with a branch across his nose. Was he trying to play or was he bring aggressive? Either way, the rhino wasn't taking any chances. Watch the exchange here.

4. A South American Magellanic penguin swims 5,000 miles every year to be reunited with the man who saved his life. Read the heartwarming story here.

5. An octopus inflates itself like a giant balloon across the ocean floor and scientists can't agree if it is hunting or showing defense behavior. What do you think?

Monday, September 14, 2015

5 Animal Species With Surprising Memories

We often think of animals as having hilariously short memories – the “memory of a goldfish”, if you will. But many animals have memories that can put yours to shame.

There are many different kinds of memory and each of them is controlled differently by different parts of the brain. Short-term memory can be thought of as the brain’s scratch pad: It holds a small amount of information for a short period of time while your brain decides whether it is worth retaining in long-term memory or if it can just fade away. When a short-term memory becomes a long-term memory, this process is called consolidation and involves physiological changes in the brain.

Long-term memory can be further divided into two main types: procedural memory and declarative memory. Procedural memory is used to remember how to do things and what objects are needed to do those things. Declarative memory is used for recall and can be further divided into memory used to recall facts (semantic memory) and events (episodic memory).Each of these different types of memories are stored in different parts of the brain. Furthermore, different types of facts (remembering faces versus numbers, for example) and different types of events (depending on if they have an emotional component or not, for example) are also stored in the brain differently. Because species differ in how we rely on our brains, it makes sense that this might be reflected in our abilities to remember in different ways.

So let’s check out some of the most amazing memories in the animal kingdom:

Do you know what all your kids and nieces and nephews are
doing right now? These elephants do. Photo by PJ KAPDostie
at Wikimedia.
1) They say an elephant never forgets. Elephants are very social animals that live in large stable herds. This has led to some incredible feats of social memory. They can keep track of the whereabouts of 30 group members at once and they can remember an animal they briefly met over 20 years ago. For an animal that lives about 50 or 60 years, this is very impressive. Elephants also have outstanding episodic memory: In 1993, Tarangire National Park in Tanzania suffered the worst drought that it had seen in 35 years. It was so severe that it killed 20% of elephant calves, compared to the average loss of about 2%. Of three herds that lived in the park in 1993, two of them were led by females that had lived during the severe droughts of 1958-61 and those herds left the park and were more successful at finding food and water. The herd that stayed was led by a younger female that had never experienced such a severe drought and that herd suffered 63% of the total mortality.

Dolphins never forget a name. Photo from the
NOAA Photo Library available at Wikimedia.
2) Bottlenose dolphins have even more incredible social memories. They, like elephants, live in complex social groups. Each dolphin has a unique whistle that it uses like a name. When they are played recordings of whistles of companions they lived with years or even decades earlier, they approach the speakers for longer than when they are played the whistles of dolphins they never met. The fact that they, like elephants, remember companions for over 20 years is much more impressive because their lifespan is only 40-50 years!

Sea lions can remember
meaningless tricks for years.
Photo by LSA2886 at Wikimedia.
3) Sea lions have amazing procedural memory. In 1991, marine biologists at the University of California, Santa Cruz, taught a California sea lion named Rio a card trick. They held up one card with a letter or number on it and another set of two cards: one that matched the first card and one that did not. Rio learned to pick the matching card to be rewarded with a fish. Everyone was impressed and she didn't do the trick again... until 10 years later, when researchers pulled out the cards and asked her to do it again. Rio had the same score in 2001 with no practice that she did in 1991 when she originally learned the trick!







Clark's nutcrackers can remember where they stashed
30,000 pine nuts.I can't even keep track of my keys.
Photo by Gunnsteinn Jonsson at Wikimedia.
4) Clark’s nutcrackers can remember the exact location of 30,000 pine nuts. This kind of superhero ability is born out of necessity: nutcrackers completely rely on their caches of food to get them through the winter. However, despite their amazing long-term spatial memory, their short-term memory is below average: they can’t even remember the color of a light for 30 seconds.

5) Chimpanzees can put your working memory to shame. Working memory is a form of short-term memory that is applied to a task. A group of researchers taught chimpanzees to do a task in which they were shown the numbers from 1-9 in random locations on a computer screen. When the numbers are covered, chimps can remember where each number was. Furthermore, they only need to see these randomly placed number for a few seconds to get this task correct. In comparison, only people that are considered savants have comparable abilities.