Category Archives: Evolution

Chaser – a dog of many words wins the ‘Dr Doolittle stamp of approval’

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This piece was guest-authored by Jess Upson who is studying Biology at Oxford Brookes University

Listen to my BBC radio chat with Malcolm. We discuss Chaser the Border collie and animal languages starting 50 seconds of ridiculous intro chat in this clip:

[audio http://www.brookes.ac.uk/lifesci/runions/DrMolecule/20130528%20-%20Animal%20languages%20and%20white%20tigers.mp3]

Do animals communicate more than we think?

Do animals communicate more than we think?

It has long been thought that we humans are ‘top-dog’ with regards to intelligence and communication, but it has recently been discovered that animals may not be as dim-witted as we sometimes give them credit for.

It turns out that if I call you ‘bird-brained’ this may not be so offensive…  Recent studies have shown that crows are one of the most intelligent animals on the planet, demonstrating extraordinary abilities of creative problem solving. These breakthroughs are beginning to shed light on how the brains of many animals work and, as much as we feel so superior, they work not unlike our own.

One of the best ways to understand the mind of an animal is observe how they behave with others of their kind. From a bee’s waggledance which tells others where the best flowers are, to the pops and whistles of dolphins whilst playing, there are a variety of mechanisms used by animals for communication. Perhaps one of the most exciting ideas is the idea that animals having a language of their own.

Studies now demonstrate that animals may communicate in what could be considered a language. A mother and infant dolphin talked over the telephone when placed in different enclosures. Elephants have also been known to demonstrate a sophisticated way of communicating, with each individual producing a unique noise, often in the sub-sonic range that humans can’t hear, and it can travel for miles. The matriarchal female can recognize hundreds of calls from elephants she knows and from huge distances away – that is the equivalent of being able to stand blindfolded in the middle of 1000’s of screaming people – like outside of One Direction’s hotel – and still being able to distinguish the ones you know!

I'll tell you a secret if you promise not to tell anyone else...

I’ll tell you a secret if you promise not to tell anyone else…

But it is not just the larger mammals that can demonstrate this. Work carried out on prairie dogs has shown their ability to produce effective warning calls, with all the details included. It was discovered that each predator had a unique call associated with it, including humans. The call could tell other individuals what the threat was as well as information like its colour and size. When a new object was placed within sight of different groups of prairie dogs, each came up with the same new warning call, showing that there may be something within their culture, a language perhaps, which allows them to convey this sort of information.

Chaser the Border collie sitting with some of her 1000+ toys

Chaser the Border collie sitting with some of her 1000+ toys

So,it is not just humans who have shown the ability to understand different forms of communication. Famously, Panzee the chimpanzee can distinguish more than 130 human words. But it looks like there is a new champion at understanding human-speak, Chaser the Border collie.Tell your dog a simple command and it may respond, but no dog has yet quite matched the ability of Chaser when it comes to understanding our language. Chaser knows the name of every single one of her toys – all 1022 of them! She also understands verbs and conjugate sentences. That’s better than I can do some mornings…

Chaser goes beyond remembering words. She can correctly respond to phrases with three parts (a noun, a verb, and another noun) 75% of the time. This sort of ability is learnt at about the age of three in humans.

It is a baffling question that if we are so ‘intelligent’, why can’t we understand animals when many appear to be able to understand us? But the mechanisms used by different animals to relay information are vast and often very complex. A dolphin clapping its fins could mean multiple things depending on the situation. For example, if you put a hand in the air it could mean you were greeting someone, or waving goodbye, or even indicating the number five, all depending on the situation.

Many animal species have vocal cords that are used for making sounds. During evolution of human speech, we have developed the ability to modulate those sounds using out tongues, lips and larynx. Many scholars are actively engaged in trying to determine how and when in our evolutionary history we developed this extrorinary ability that sets us apart from other animals, including those like the great apes who possess vocal cords.

Talk to the animals

Talk to the animals

Some still argue that the idea of species other than humans communicating through a language is far-fetched. But we are only just beginning to understand the subtlties and intricacies of animal communications. So is animal language really as fictional as Dr Doolittle’s Pushmi-pullyu?

Can animals evolve to survive climate change?

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Many who might be skeptical that climate change is a problem that results from Human activities will say, as a last refrain:

“Oh, anyway… animals can just evolve to survive rising temperature.”

But is this true?

funny-hot-dog-melting-picsCharled Darwin had a dreadful time trying to convince his Victorian peers that evolution by natural selection was a real process in nature. This is because he could not demonstrate unequivocally that is was happening. And the reason that he could not demonstrate that it was happening is that it happens slowly.

I mean, part of the process of evolution results when organisms adapt to new and changing environments. This adaptation takes place over hundreds or thousands of generations. The snow leopard will not just simply decide that it’s too warm and shed its fur so that all is hunky-dory.

Thinking about Human generation times – arguably 20 years – hundreds of generations means that it takes 5000-10000 years to notice even very small changes that result from mutation of genes that might confer an evolutionary advantage in a given situation. Most organisms have shorter generation times but even the smallest adaptations gotten through evolution will realistically take 1000s of years.

I saw a calculation recently that showed that animals can ‘evolve’ at a rate that would make them able to adapt to temperature change of 1 degree celsius per million years. Present calculations show that our average temperature on earth will likely rise by 4 degrees celsius by the end of this century. Evolution needs to work, uh, let’s see… (4 degrees in 87 years = 1 degree in 21.75 years, and 1,000,000 / 21.75 = 45977), 46,000 times faster than it does now. That isn’t going to happen.

The funny thing is that an average temperature rise of 4 degrees doesn’t seem like that much to us. It will have devestating consequences for our planet, however. Ice sheets will melt and the water cycle will be thrown completely out of kilter with consequences like worsening weather, flooding, and drought like we are starting to experience now.

familyAnimals and plants that have evolved to survive in their special environment (and that’s generally what evolution has done) might survive the onslaught of climate change for a while by moving to adjacent environments where it is (choose one – wetter / drier / warmer / colder) but that is a short-term fix.Plants and animals that are adapted to survive in desert environments are separated by hundreds of millions of years of evolution from those that are adapted to survive in very wet conditions.

Our snow leopard really won’t find the prey items that it needs to survive if its habitat warms, and it can’t simply pick up and find a new home like the Bevely Hillbillies did (Kin folks said, Jed, move away from there…)

Your DNA doesn’t contain as much junk as your teacher says it does!

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New scientific evidence, released this week as the ENCODE project, tells us that our DNA has a lot more information in it than we had previously expected

Listen to my BBC radio chat with Malcolm. We discuss the ENCODE project starting at 47 seconds into this clip:

[audio http://www.brookes.ac.uk/lifesci/runions/DrMolecule/20120911 – ENCODE and a gene for trotting.mp3]

Follow this link for a good GuestBlogged essay on the information contained in DNA.

Whales committing suicide en masse… why?

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On a recent weekend, whales stranded themselves on 4 different beaches around the world. Why do they do this?

Listen to my BBC radio chat with Malcolm (actually, with Nick Piercey this time. We discuss whale strandings starting at 25 seconds into this clip:

[audio http://www.brookes.ac.uk/lifesci/runions/DrMolecule/20120904 – Beached whales and tree diseases.mp3]

Whales and dolphins stranded on a beach

Stories about animals committing mass suicide are just not true – whether the animals in question be lemmings or whales. On of the central tenets of evolutionary biology is that the gene is selfish. Mass suicide is not a biological imperative – animals seek to reproduce and raise their young in all cases. While it is true that evolutionary theory talks of a ‘struggle for survival’ and ‘survival of the fittest’, there is no indication that whales that strand themselves are at less than peak fitness. So, although the reasons for whale strandings are unclear, the thing that you can be sure of is that whales are not ‘committing suicide.’

An engraving depicting three beached sperm whales that dates from 1577

Why then do these terrible tragedies occur? It is easy to point the finger and say that man is to blame. That might be partially true, and I will explain why in a bit, but there have been documented whale strandings since well before we filled the ocean with human technology that might confuse whales.

What is usually true is that it is the ‘toothed’ whales like pilot and sperm whales that beach themselves. These are the whales who hunt and eat meat like fish and seals. Larger whales such as Blue whales who filter zooplankton (the baleen whales) much less commonly beach themselves. The suggestion here is that it is the act of hunting in packs for animals that shelter in shallower waters that contributes to whale strandings. I hear you say, ‘But whales aren’t stupid!.’  Far from it, I think I made the point already that they wouldn’t have survived this long if something as common as a bit of shallow water was going to confuse them so much that they died.

Humans rescuing beached whales

My contention is that shallow waters have probably resulted in confused and stranded whales throughout evolutionary history but that it is exactly this that should have selected for whales that are exquisitely able to survive in these environments. Orcas have been observed to beach themselves as a hunting strategy. They catch seals on the beach and wait for the next wave to re-float them. This is a learned / evolved behaviour that not all whale species have acquired. Evolution is a slow process – especially for large, long-lived organisms that take years to produce successive generations. That’s why deer haven’t ‘evolved’ the ability to avoid cars. No predators with which they have evolved move as fast as a car, and cars have only been around for a few decades. I can imagine that if we kept driving cars at deer for many thousands of years that the ability to avoid them would evolve in deer.

OK, so whales have evolved to survive in shallow water environments and should be able to avoid being beached. It still happens – and it happens much more commonly on some beaches than on others. Scientists postulate that when pods of hunting whales stray into unfamiliar territory, they can become confused. This confusion is most prevalent in areas where the angle between beach and sea bottom is very shallow – it does not, therefore, reflect the sound that whales make as a navigation aid back to them and they remain unaware that they are dangerously close to the beach. This situation combined with strong current or tides is why whales end up high on beaches.

A Long-finned Pilot whale being rescued by crane

Whale rescue agencies have been set up around the world and are staffed, generally by volunteers, so that they can be mobilized quickly when whales beach or, even better, when a pod of whales gets close to a stranding site. Whales have not evolved to support their own weight for very long (I even find it a bit uncomfortable when I lay on the couch for more than a few hours watching TV!) and they quickly become very ill when beached. Even when rescued, they commonly remain confused and often re-beach themselves.

I mentioned at the top that human human activity might play a role in the increasing number of whale strandings that are being observed. In early September this year (2012), pilot whales beached themselves at 4 different locations around the world. That just seems like too much of a coincidence. One factor that seems to cause a great deal of confusion in whales is noise. And man do we fill the oceans with noise. Not only the din caused by ships engines but, increasingly, SONAR from military exercises. These sounds can be louder (240 decibels) than any sounds on land including jet engines and rock concerts. Think about whales who have evolved to navigate using sound – hear for yourselves the plaintive whale sounds that some species can detect from hundreds of miles away. The incidence of whales beaching increases after military exercises involving SONAR, and scientists have observed that many of the whales involved in these beachings have acoustically-induced hemorrhages around the ears.

We must consider the natural environment of these animals before we deploy things like load SONAR for military purposes – is it worth it?

A breaching humpback whale

While I’m on the topic of what we do to the whales environment, watch this amazing video of a humpback whale being rescued from a fishing net. I just about didn’t watch it because I was concentrating on whale strandings when I found it. It leaves me with mixed emotions. On the one hand, the majesty of the animal and it’s apparent cooperation with the humans. On the other, what if they hadn’t encountered the whale. It would just be a statistic on its way to extinction.

Human evolution… our ancestors weren’t fighting dinosaurs!

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It makes for good TV though…

Listen to my BBC radio chat with Malcolm. We discuss our Human ancestors after 2 minutes of ridiculous intro chat in this clip:

[audio http://www.brookes.ac.uk/lifesci/runions/DrMolecule/20120814 – Human evolution and Florence Nightingale.mp3]

A happy looking chap – of an entirely different species

I grew up watching televised accounts of our ‘cavemen’ ancestors battling giant man-eating dinosaurs. In fact, those battles didn’t happen – not even close. Dinosaurs went extinct 65 million years ago and our ancestors have evolved to walk on two legs and look something like us only in the last 2-3 million years. The very earliest primates started to evolve from early mammals 85 million years ago and would have overlapped with the dinosaurs somewhat.

We all – excepting Simon Schama – experience this sort of historical time dilation when thinking about things that happened before we were born. At its extreme, the child who asks, ‘Mommy, when you were little did you see dinosaurs’ to the usual adult confusion about what century events happened in. Modern humans of our species, Homo sapiens, have only been around for the last 400,000 years, and have only started to behave modernly during the last 50,000 years. It is during that period that we see the rise of symbolic culture and language.

Charles Darwin and Alfred Russell Wallace shocked Victorian sensibilities

That’s me on the lef…uhh, the right.

when they proposed that Humans had evolved from apes. The very idea was lampooned in ‘the ascent of Man’ images of the sort that are now known to depict one of the most brilliant and impactful scientific ideas ever. Evolution is a fact. I proceeds so slowly, however, that it is difficult to observe in action. The giraffe that might benefit from having a longer neck doesn’t just grow a longer neck. Over hundreds or thousands of generations, giraffes that have slightly longer necks are slightly more successful at foraging in trees than their slightly-shorter-necked contemporaries. These more successful foraging giraffes are likely more fit and are better able to pass their genes into the next generation. By a series of very small increments, giraffe offspring in subsequent generations will have slightly longer necks. That process continues until the longer necks are no longer an advantage, i.e. until they become too heavy or breathing becomes difficult. Evolution is a slow process which results in ‘fitter’ organisms but it regulates against ‘runaway’ selection – it is just physically impossible for a giraffe to have a neck any longer than they now are – the animal would become ‘unfit’ in many other respects.

Back to Human evolution. It really isn’t as simplistic as the idea illustrated that a chimpanzee turned into a caveman etc. After all, chimpanzees still exit. Why? The answer is that in the deep dark past – millions of years ago – we shared a common ancestor that resembled a small primate. Some offspring of the ancestor began to evolve towards Human form while others evolved towards modern chimpanzee form. Evolution is a branching process and one of the biggest drivers of branching is when offspring find themselves in different environments where different characteristics will help them survive and reproduce better. What was the original main distinction between the Human branch and the chimpanzee branch? Answer – the ability to walk upright in our branch (or to walk on a branch in the chimp’s case, get it?). The Human branch moved onto the savannah where individuals who could stand or walk upright had a definite surveillance and hunting advantage just by being able to see further. The chimp branch remained in the forest where climbing ability and smaller stature were an advantage (have you ever seen a chimp climb – holy baloney?). Gradually and over thousands of generations, animals in each branch evolved to more closely resemble either modern Humans or chimpanzees.

Branches in Human evolution – about a million question marks still remain

So, let’s consider the Human branch. Why did it stop branching along the way? That’s a trick question. The answer is that it didn’t stop branching. As Human ancestors spread out of Africa into Asia and Europe, populations became isolated. Remember, we’re talking about migrations that take generations – you didn’t just jump on Air Africa and fly to London in those days. Isolated populations gradually differentiate – as you well know if you’ve ever sat in a pub with a Scotsman, an Irishman, a Welshwoman, and an Englishwoman. Language is one of the first things to start changing and differences are obvious over very fine geographical scales. Physical attributes take longer to evolve but they do and they have resulted in many branches of the original one that lead to modern Humans. Look at an enlarged view of the image to the left – we (Homo sapiens) are only one of several different species which have existed and even co-existed during the last 2 million years. Most recently, we shared Europe with Homo Neanderthalis – and I mean in relatively modern times, until about 30,000 years ago.

So what ever became of the Neanderthals? Well, they went extinct. This often happens when closely related species try to co-exist. Perhaps

Clap for the ape-man

we could have continued to co-exist but similar species usually require what is called a ‘niche’, that is, they need to have their own environment, or food source, or method of survival. Remember that Humans and chimpanzees can co-exist because they get the trees and we get everything else. If the chimpanzees tried to use our resources, a Planet-of-the-Apes situation might ensue. More likely, however, is that they would go the way of the Neaderthals and not be heard from again. Hey, we’re not even very tolerant with members of our own species who try to take our land from us.

A debate continues about just how close our species and the Neanderthals really were. We still harbour a good deal of Neanderthal DNA and scientists are trying to work out whether that’s because, as some think likely, the species interbred where their ranges overlapped (in Paris after a romantic night out on the left bank, for example), or whether that’s just leftover DNA from our common ancestor back at the ranch point.

In any case, ‘no Sweetheart, Mommy didn’t see dinosaurs when she was little.’ She was closer to meeting Human-relatives of a completely different species but even that’s probably pushing it a bit.  How old do you think Mommy is, anyway!?