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Showing posts with label natural world. Show all posts
Showing posts with label natural world. Show all posts


 Death is hard. As a human, it is perhaps the hardest thing that we can face, and yet you never really understand it until it happens to you. 

Often, the remarkable thing is that - no matter how long you anticipate it - it happens suddenly. There is sick lurch of loss and yet, at the same time, your mind is left reeling and scattered. It's a strange contradiction to be confronted with death. That person - the person you know - is gone and what is left is some sort of husk that bears no resemblance at all to what they are. Yet, as you try to process grief, the most confusing (and yet most comforting) part is that what that person is hasn't left at all. They still feel real and present and there. It's just that you no longer have the opportunity to interact with them any more, and it is that gut-wrenching homesickness that takes the greatest toil
Lemony Snickett perhaps describes it best:

“It is a curious thing, the death of a loved one. We all know that our time in this world is limited, and that eventually all of us will end up underneath some sheet, never to wake up. And yet it is always a surprise when it happens to someone we know. It is like walking up the stairs to your bedroom in the dark, and thinking there is one more stair than there is. Your foot falls down, through the air, and there is a sickly moment of dark surprise as you try and readjust the way you thought of things.”

It is clear that death is an incredibly strong and complex emotion so, when we look into whether animals too can feel the same emotions, it is an important place to start.


 The Elephant is perhaps one of the most intelligent and emotive animals that we know of.

It's commonly regarded that elephants can show joy, anger, grief, compassion and love. Bonding into close matriarchal societies, they are knitted together -rather like humans - by how long their children take to grow into adults. They are often compassionate: for example herds have been observed to slow down their entire pace to match the weakest member. There has been an instance where an elephant physically put her life in danger to try to save a Rhino calf that was stuck in the mud, despite her being attacked by the aggressive mother who misread her actions.

An Elephant Graveyard in The Lion King
When it comes to how deaths are handled within elephant herds, there are many observational tales that circulate  - academically and otherwise - to the point where they become almost urban myths. One of the most popular concepts is the idea of a elephant graveyard, where ageing and sick elephants willingly go to die. This myth has since been debunked - instead 'graveyards' were shown to simply be sites where famine or poisoning had caused the death of a group of elephants all at once. However stories of grieving elephants are still passed around.

Mother Elephants have been observed staying with their dead babies and showing signs of distress. One mother tried to lift up the dead body and move it with her feet, staying with it for around an hour in what might be described as a state of sadness or shock. Some elephants have stayed with dead friends for up to three days at a time, refusing to move from them. Old dying elephants have been cared for by the whole herd when they fall, as the herd try to heave them up with their tusks and tenderly provide food and water for the ill animal, before watching it die. In a case such as this, when the rest of the herd moved on, a mother and her calf remained with the body for a whole day. In other examples, elephants have displayed what Charlie Mahew tentatively be called 'burying behaviour', where they toss dirt and leaves over the carcass of a dead elephant. In another anecdote from the 1940s, George Anderson reported that he shot a bull elephant that would repeatedly break into the government gardens of Kenya. The meat of the elephant was carved and given to the tribes-people and afterwards he dragged the carcass half a mile away. To his surprise, that night other elephants found the body, took a shoulder blade and a leg bone, and returned the bones to the exact place where the elephant was killed. Some people believe that elephants can recognise their own herd members' bones and will ritualistically visit them repeatedly, or will at least pick the bones up and even carry them in an effort to recognise them or pay homage to them.
Surely all of these behaviours show us that elephants can mourn?


Well so far, so much conjecture.

Picture by Sarah Skinner
No matter how many stories circulate about these apparent mourning behaviours, comparatively little scientific studies have been conducted to back them up. For example, we don't know whether elephants actually know what death is as an abstract and inevitable consequence of life. Is their grief one that has this understanding, or is it only a recognition of loss? Does it matter? And how true are any of these stories?


Karen MCComb, Lucy Beker and Cynthia Moss attempted to answer this question, creating a study of how several herds of African elephants interacted with the ivory and skulls of their own species, including some of their own matriarchs that had died within 1-5 years, as compared to wood and other dead animal skulls. All exhibits were washed to prevent any scent or human interaction lingering, and all elements were mixed and presented as per usual fair scientific practice. Primarily, they wanted to eitehr confirm or debunk the myth that elephants could recognise their own dead relatives, and that elephants took special interest in elephant bones above all else.
These assumed traits are important in identfying whether elephants recognise death, or even mourn, more than many other animals. Chimpanzees, for example, do have a complex interaction with deceased members of their own species, but seem to completely lose interest when those members decompose. Elephants however, it was suggested, carry this emotional recognition of death even to the skeltal stage. 
By using controlled experiments, they were able to prove that elephants take a special interest in the bones of their own kind which cannot simply be explained by bones being a 'novelty'.

An Elephant Skull
Elephants displayed a marked preference for investigating and interacting with the skulls and ivory of other elephants in preference to skulls from other animals or natural objects. The ivory gained the most preference and was even investigated with marked preference over the skulls. They suggested that 'the interest in ivory may be enhanced because of its connection with living elephants, individuals sometimes touching the ivory of others with their trunks during social behaviour'. This is especially interesting because the ivory was smallest in size and simplest in shape. If the elephants had been drawn to investigating the largest and most complex structures, they would have surely chosen skulls, and if they were drawn to the rarest structure, it would surely have been the Rhinoceros skull.

Importantly, the experience seemed to debunk the myth that elephants selectively recognise and revisit the bones of their relatives. There was no strong preference for investigating the Matriarch's skull over the other elephant skulls present. So, while they may not specifically select the skulls of their own relatives for investigation, the strong interest in ivory and the skulls of their own species mean that they would be highly likely to visit the bones of relatives who died within their home range. In this case, I would even say that it would be true of humans. If you're presented with the bones of a stranger or a dead relative, it is an unusual individual who can recognise them out of nowhere after all, yet the presence of a human skeleton is a natural cause of sadness and unease. However, while a human might perform some form of ritual for the body - such as reburying it or leaving a token on it - it is still unknown how far elephant behaviour is simply a sensible evolutionary curiosity or more of a genuinely emotional and respectful response. To further complicate things, this behaviour isn't unique to every elephant: in the end it is a very personal display.


In the end, a lot more study has to be done on this subject. And Elephants aren't alone in potentially mourning, of course.

Throughout the world, many intelligent animals display the behaviours of grief - whether this means a true 'mouning' and recognition of death, or simply a depression following the loss of a close companion. Even some less intelligent animals, such as ducks, have been shown to miss a departed companion so much that they never fully recover. 

To this day I still remember by own experience of viewing animal mourning behaviour.
I was 12, on my first ever holiday abroad to Tenerife where we took a catamaran to go view the dolphins (hopefully!) playing in the sun and sea. While no dolphins showed themselves that day, we experienced something far rarer and more poignant. Emerging from the sea, a whole pod of medium-sized sleeping whales swam around and under our boat. They were all black but for one striking small bleached-white figure: a dead baby being carried on its mother's back. The guide told us that when the calf died it would be carried in this way for some weeks before finally being let go to drift to the bottom of the ocean.

It's very difficult indeed to know what thoughts or emotions pass through these animals when they display such behaviour, but the effect is always haunting. At the very least, it reminds us what it means to be human.



Sources
- African Elephants Show High Interest in the Skulls of Their Own Species: From Biology Letters (McComb, Baker, Moss)
- Echo: An Elephant to Remember - Elephant Emotions (PBS)
-Of Mournful Elephants and sorrowful chimpanzees (How Animals Grieve by Barbara J King)
- Animal Grief: How Animals Mourn by David Alderton
-Elephants Really Grieve Like Us (The Daily Mail)
 The world is doubtlessly beautiful, but sometimes beauty can be found in odd an unconventional forms.

So it is with perhaps one of the more repulsive lifeforms on our earth: the slime mould. But despite its rather unflattering name and underwhelming looks, this creature is both fascinating and have given us unique insights that will help us in our futures.


Slime Moulds
via Discover Magazine


 Eugh...

You're wandering through the woods, minding your own business. The leaves are dark and wet against your feet but hey, you thought ahead and wore wellies this time - nothing can stop you! You tilt your head up and close your eyes as you breathe in the fresh, clean, damp air. Distracted, your foot catches in the hook of a root and, before you know it, you're tripping and falling. You push out your hands out in front of you to break your fall and your palms connect with..this.
Ew.

So what are they? 

There's no surprise in where slime moulds got their names from. Slimy and toxic-yellow, they cover rotting wood and eat fungi. They have no brains or nervous system and so share the most in common with amoebas. Aside from their generally unpleasant appearance they might be entirely unremarkable, it it wasn't for the way they move and navigate the world around them.



Why are they so important?

Slime moulds navigate their way around the forest floor searching for food in a very interesting manner, which has given scientists great insight about efficiency and how we might best be able to program robots or build transport systems.
They move using pulsing tendrils called psudopods which, through a clever organization can navigate the world without a brain:


"Every part rhythmically expands and contracts, pushing around the fluid inside. If one part of the plasmodium touches something attractive, like food, it pulses more quickly and widens. If another part meets something repulsive, like light, it pulses more slowly and shrinks. By adding up all of these effects, the plasmodium flows in the best possible direction without a single conscious thought. It is the ultimate in crowdsourcing."- Ed Yong

This mimics how other creatures, such as humans and ants, navigate the world. But in this case the lack of a brain is what is remarkable. Human hikers might explore woodland and fields and, over time, trails are stomped into the ground by many trudging feet. The trails that are the most effective remain, trodden into the grass, and those that proved inefficient are difficult are used less and so gradually overgrow once again. This way the less efficient routes are gradually erased and the more efficient routes are reinforced. When ants go exploring they do something similar using pheremones. They lay out pheremones to plot their path so that they know where they've been before and this discourages other ants from trotting down pointless routes. When the ants find something they like, they pump out another pheremone which attracts other ants down that route. This way efficient routes are reinforced and many a full ant belly is had by all.
The brianless slime moulds do they same: they send out slime trails that explore routes. The inefficient paths are abandoned and lesser slime is left to significy that these routes should not be used again, whereas when an efficient and lucrative route is discovered more stronger slime mould is encouraged down it, emphasising its efficiency.

This was put to the test as scientists placed slime moulds on a map of Tokyo where they had placed food points where all the major cities were. They found that despite not knowing their environments or having any opportunity to plan, Slime moulds tracked out the most efficient routes which - amazingly - matched up with the road systems all ready put in place. By sending out trails to all possible configurations and then drawing back to leave only the most efficient, the slime moulds became city planners.
The same could be done with maps around the world.



This ability also allows the slime moulds to navigate mazes, which is an important development as it can be a lesson used to assist in the programming of robots. Because it's too complicated and uses too much memory to program robots with pre-programmed maps or for them to build up maps as they explore, one way of allowing them to move freely without getting trapped is to program in an imperative to 'avoid the past', as slime moulds do. By doing so like slime moulds sending out all their trails and then reducing them down, robots can freely explore and then naturally reduce down their movements to use only the most efficient routes.

These are only some of the large variety of experiments that are being conducted with slime moulds. These humble gooey creatures are set to teach us a heck of a lot about decision making processes, efficiency, and how best to plan for our collective futures.



Sources
-Slime mould memories: discover magazine
-'Slime mould make decisions like humans'
-'Slime mould attacks simulate Tokyo rail networks'
-BBC Youtube: Slime mould time lapse
-The Gaurdian 'Let Slime moulds do the thinking' 
 


And now for something completely different:

Next week I will be packing up and trotting off to Download Festival, whereby I will participate in the noble tradition of standing in a field and getting rained on for three days straight.

On a side note, did you even know that there is wellie-related porn? I certainly didn't until I did an image search, so I hope you appreciate this picture!

As a result, I won't be able to contribute next Sunday. But fear not, regular programming will resume from then on...