How Do Springbok Keep Cool?

www.ultimate-africa.com

Springbok (Antidorcas marsupialus) live in South Africa which, obviously, can get very hot during the day. Many animals that live in Africa tend to try and stay in the shade during the day to keep cool but there are also those that store heat in their body during the day and then let their body temperature decrease rapidly during the night so that the next day they can do the same again. This technique is called adaptive heterothermy and has been seen in often in captive animals. Fuller et al (2005) carried out a study to see whether this technique was also found in wild animals and decided to investigate a free ranging herd of Springbok.

For this study some very impressive technology was used to save time and also to make the results more accurate. Small data recorders where implanted inside each animal and these measured the body temperature of the animals every 30 minutes for a year. If this technology had not been used then the Springbok would have had to have been captured every 30 minutes, every day for a year. Not only would this be very time consuming, it would also affect the results of the study because the animals would likely be stressed about being caught all the time. While the animals were doing their own thing for a year, the team measured the temperature of the air, the wind speed and the humidity so that at the end of the year the body temperature could be compared with the weather.

If the Springbok used the technique described above then the body temperature would be expected to change often with very wide swings. They actually found that the opposite happened. No matter what the weather was like, the body temperature of the animals hardly changed. This technique is called homeothermy and it was a very surprising find. Even stressful events like giving birth did not affect the body temperature a great amount.

This study highlighted a very important point to consider when carrying out experiments on body temperature. When animals are roaming free in their natural environment they often use behavioural mechanisms to change body temperature instead of using physiological mechanisms such as adaptive heterothermy. Behavioural mechanisms like this include huddling together when it is cold or finding a shady area when it is too warm. Fuller and team made a mistake in this study because they did not watch the behaviour of the animals, they only took physiological measurements. Hopefully further studies will be carried out that will learn from this mistake!

References

Fuller, A., Kamerman, P. R., Maloney, S. K., Matthee, A., Mitchell, G. and Mitchell, D. (2005). A year in the thermal life of a free-ranging herd of springbok Antidorcas marsupialis. J. Exp. Biol. 208, 2855-2864.

A Decade Long Marine Census Comes To An End

Yeti Crab - Census of Marine Life

The Census of Marine Life which started in 2000 has finally been completed. It is estimated that during the census 20,000 new species have been discovered, bringing the number of known species to nearly 250,000. The decade long project cost £413m and aimed to find out what lived, lives and will live in the oceans. It involved more than 540 expeditions with over 2,700 researchers and used many new types of technology. Fish were tagged and seals were fitted with monitors to record when they dived. Acoustic systems were used to measure fish populations.

Dr Ian Poiner, the chairman of the project’s scientific steering committee, told the BBC “All surface life depends on life inside and beneath the oceans”. This is literally true because we know that life evolved from the oceans and the very first life forms were aquatic organisms. Back then the atmosphere did not have everything they needed to survive but the water did. It was a while before the air contained the nutrients that were needed but eventually life began to evolve on earth. It is thought that there could still be many undiscovered species in the oceans and there could be at least a million of them in total.

Many wonderful species have been discovered during this census, including a Jurassic Shrimp that has thought to have been extinct for at least 50 million years and a crab which has been named the Yeti Crab (see the picture at the top of this post). However, it wasn’t just large organisms that Dr Poiner’s project looked for. The census included trying to tell tiny microbes apart using genetic sequencing. If you thought that a million organisms was a lot then you will be surprised at how many different types of microbes are thought to be in the water – one billion. Hopefully the Census of Marine Life will serve as a base for us to build on to try and preserve marine life.

Source - MSN News

A New Species of Giant Elephant Shrew?

An elephant shrew in an undated photo released September 21, 2010.
Credit: REUTERS/Zoological Society of London/ Handout

Researchers in a remote Kenyan forest, the Boni-Dodori forest, think they may have discovered a new species of Giant Elephant Shrew (Macroscelidea). Further genetic analysis will be carried out by the Zoological Society of London and the Kenya Wildlife Services (KWS) to determine whether this is actually a new species or whether it is a new variety of a current species.

Interestingly, the Giant Elephant Shrew is more closely related to elephants than shrews. Unlike many small mammals, these Shrews are only active during the day. They use their long snout to search under leaf litter where their food source, invertebrates, can be found and eaten with their extremely long tongue. It is the long snout that originally gave the Elephant Shrew their name.

Scientists launch many expeditions a year to research biodiversity around the world and this is especially needed now that forests take up a much smaller area of the world than they did 40 years ago. This is particularly dangerous as loss of habitats can cause animals to become endangered and even extinct, especially if they are not as widespread as some animals. The Giant Elephant Shrew are among the list of endangered animals and the discovery of a new species is a very significant discovery. Elephant Shrews tend to be more adapted to areas where water and food is available all year round, such as coastal forests, and destruction of the forests can be drastically dangerous for the survival of these species.

References:

The African Wildlife Foundation (AWF)

http://www.reuters.com/article/idUSTRE68K2SX20100922

Thanks to fellow zoologist Nicola for pointing this story out to me!

Why Do Lions Roar While Cats Meow?

If you don’t already know (and why would you?), cats are my favourite animals. I love small cats and large and my favourite cat is the Tiger. I was therefore very interested when I saw this article on the BBC website. In it, Ella Davies explains why bigger cats, like Lions and Tigers, roar and Wildcats meow. I have wondered this for a while and find it very interesting so I thought I would tell you all about it.

In a recent study, two scientists from the Alexander Koenig Zoological Research museum in Germany analysed the calls of 27 different species of cat and investigated whether they were affected by the habitat that the cat lived in and the size of the cat. While previous research found that it was the cat’s size that influenced the pitch of its calls, this study showed that cats living in open areas (e.g. lions, servals and cheetahs) had deeper calls than those living in dense habitats such as forests (e.g. marbled cats, wildcats and clouded leopards).

Previous research has shown that high pitch calls can be disrupted by dense vegetation and low pit calls are disrupted by air turbulence in more open spaces. Other scientists believe that the reason is actually because big cats can produce sounds at a lower frequency and this is why lions roar while cats meow. However, this study investigated this theory and found that body weight had no effect on how deep the call was.

I have found the published works of this study and plan to read through it for some more information. I will get back to you! You can find the article at the BBC here.

Kin Selection and Evolutionary Stable Strategies in Vampire Bats

This morning I have been reading about evolutionary stable strategies and one of the examples given in this week’s lecture was reciprocal food sharing in Vampire Bats so I have done some reading on it. I think it is really interesting how these bats behave so I’m going to tell you a bit about it from what I have learnt! First we need a definition of what an evolutionary stable strategy actually is. If most members of a population adopt the same strategy and this cannot be bettered by any other strategy then it can be defined as an evolutionary stable strategy (or an ESS). These are frequency dependent and this is because the successfulness of the strategy depends on what the organisms around you are doing. It can also depend on whether there are “cheats” around as these can take advantage of the ESS and lead to its downfall.

The research I read this morning was done by Gerald S. Wilkinson in 1984 and it is an example of an evolutionary stable strategy in the Vampire Bat (Desmodus rotundus). Vampire bats who do not manage to get a blood meal during the night often beg blood from successful individuals in the roost during the day. The successful individual may regurgitate some blood for the other bat to take in and therefore increase its chance of survival. Wilkinson investigated how this behaviour was an evolutionary stable strategy and came up with three conditions that need to be fulfilled in order for it to be considered an ESS. These were:

1. There must be enough repeated regurgitations between pairs of bats so that they each get a chance to regurgitate and receive blood
2. The benefit of receiving the blood must be greater than the cost of donating
3. Donors need to be able to recognise and not feed previous bats that have not reciprocated

When doing a census of the roost, it was found that the main social unit is the female group. This is because males tend to leave their natal group when they become one year old. Female bats tend to stay in their maternal groups and this means that female groups are usually made up of close relatives with only a few exceptions.  Most of the regurgitation of blood occurs between a mother and her offspring and any others tend to be between animals that are frequent roost mates. Blood is donated preferentially to individuals that are likely to die in the next 24 hours if they are not fed. This shows that the giving of blood is to increase the chances of a survival of a related bat. If the bat survives to adulthood it is more likely to reproduce and pass on the family genes. This is called Kin Selection and is quite common in the animal kingdom.

References

Wilkinson, G.S., 1984, Reciprocal food sharing in the vampire bat, Nature, Vol 308, pp 181-185

A Sad Fate For This Organism But It May Give Hope For Others

Image from BBC News here.

This Saola (Pseudoryx nghetinhensis) was captured by villagers in Laos in the middle of August this year. They nicknamed it the “Asian unicorn” even though it has two horns instead of one. These animals are extremely rare and have never before been seen by anyone in the wild or in captivity. The only information we have about this mysterious animal was gotten from photographs taken by local villagers.  It is believed to live in the Annamite Mountains of Laos and Vietnam and this is where this adult male was found. It was brought back to the village where villagers took photos of it and notified the authorities. The Bolikhamxay Provincial Agriculture and Forestry Office arrived in the village too late and the Saola unfortunately died as it was weak from its capture. A spokesperson however insists that although the death of the Saola is unfortunate, at least it confirms where the animal still lives so that conservation efforts can be strengthened. The carcass of this animal was taken back to the labs for further analysis. Once more information has been gathered on the biology of this species, it will be easier to conserve it and maybe even take some into captivity where breeding programmes can be implemented.

The Saola was delared a new species in 1992 after it was found in Vietnam and its DNA was analysed. Although it looks very much like an antelope, it is thought to be more closely related to cattle. The IUCN red list of threatened species lists the Saola as critically endangered and it is thought that the number surviving may only be 24-100. The last time any of these animals were seen was in 1999 when automatic camera traps photographed one in Laos.  The Laos authorities have now urged other Laotian villagers not to capture any Saola due to the rareness of the species. Awareness of the species needs to be raised in the local areas to prevent any more deaths from occurring although it is still unclear why villagers captured this specimen in the first place.

Bear Is Seen Practising Yoga

Source - Guardian

A bear at Ahtari Zoo in Finland has been caught on camera doing a stretching routine that looks very much like yoga! Santra is a female brown bear (Ursus arctos) and was caught on camera performing a 15 minute long stretching routine by a Slovenian tourist.

She started off with both legs in her hands in a V position. She then held up her left leg only and held it for a bit and then her right leg only and left it for a bit. She then repeated the routine. Throughout the 15 minutes Santra looked focussed and calm, exactly like a human does when they’re practicing yoga. A yoga teacher from Bristol told the BBC that the bear was doing expert postures and it was obvious that she was an advanced practitioner. He thought that she might have started doing yoga to keep herself sane.

I’m not sure about yoga, but I think that this routine could be a sign that Santra is not happy in her environment. If she does it often then it could be a stereotypical behaviour. These are behaviours that are repeatedly performed and show that the welfare of the animal may be below standard. If it is a one of then it might just be a coincidence.

Read the story here and see more pictures of the routine here.

The National Trust Hunt For a New Snail Species in Britain

The National Trust has begun a search for a snail which originally comes from the Mediterranean since two colonies have been found in the UK. It is thought that the snail hitched a ride to this country on imported Italian and Greek stones over 100 years ago. A nationwide hunt is now being conducted to find where else this snail lives. The snail has no common name but its scientific name is Papillifera bidens. It is around 13mm long and has a pink/grey spindle shaped shell. There is now dispute between the two sites where the snail was found over whether it should be named the Cliveden snail or the Brownsea snail.

P.bidens is believed to have come to Brownsea Island on rock which was imported from Greece in the 1880’s. It is thought that they arrived at Cliveden later, in 1896, when brick and marble was imported from Rome. Since they arrived, the snails have not ventured far from each site and the two colonies have only just been discovered. They were discovered by volunteers that were cleaning statues for the organisation in 2008 on the Cliveden estate in Buckinghamshire. The National Trust is now searching all of its properties to see if the snails are living anywhere else in Britain, the theory being that the Victorians and Edwardians imported many statues, rock and brickwork from the Mediterranean and so this snail could have hitched a ride to elsewhere in the country. The National Trust for Scotland and English Heritage are also helping with the search.

The public have also been asked to keep an eye out for individuals of this species and upload photographs to this Flickr site where experts will verify whether the snails belong to this species. They have said that it is quite possible that the snail has spread to elsewhere in the UK due to items from gardens of grand houses being sold and put in household gardens. So far only one photo has been uploaded to the Flickr page and that is the one put there by the National Trust and can be seen at the top of this post!

(sources - BBC News and The Guardian)

The New Species of Miniature Frog (Microhyla nepenthicola)

As promised, I have been researching the species that I posted about yesterday morning. Today I found some more information on the Miniature Frog (Microhyla nepenthicola) which was discovered in Borneo in August of this year. The article I found can be found here.

This species of frog was found inside a species of pitcher plant named Nepenthes ampullaria. These plants live in areas which have nutrient poor, acidic soils and this makes it difficult for them to take in the nutrients they need. They have solved this problem by developing cavities that trap insects and kill them with a liquid. The frog has taken advantage of these cavities. It deposits its eggs on the side of the pitcher so that when they hatch, the tadpoles can enter the liquid in the cavities and grow.

M. nepenthicola is part of an amphibian family called microhylid. The family consists of frogs that are under 15mm long and according to Conservation International (CI), this species of frog is the smallest that has been discovered in this family. Adult males measure from 10.6 to 12.8mm long. Their amazing size can be seen on the picture below which was taken by Indraneil Das/ Institute of Biodiversity and Environmental Conservation and shows the frog on the side of a penny. It was thought that their tiny size could be the reason why this species has not been discovered until now. However, specimens that are the same species as this frog have been found in museum collections that are over 100 years old. They were not recognised as a new species and it was thought that they were merely juvenile frogs from other microhylid species.

Scientists discovered the frogs by tracking their call. It has been discovered that individuals of M. nepenthicola start singing at dusk with harsh notes. They sing for a few minutes at a time with intervals of quietness. The singing starts when the males gather within and around the pitcher plants and peaks in the early hours of the evening.

This discovery is part of the campaign that the CI and IUCN’s Amphibians Specialist Group are running. The campaign aims to rediscover many species of amphibians that are considered “potentially extinct”. According to the IUCN, these “lost amphibians” may still be living in remote parts of the world. The conservation status of amphibians will likely be highlighted with this campaign. Numbers of amphibians are currently declining world-wide due to use of pesticides, habitat destruction and other man-made problems. At least one third of all amphibians are currently classed as “threatened”. If you are interested, the campaign can be followed here.

New Species According to MSN News

This morning I noticed an article on MSN News (news.uk.msn.com) about several new species that have been discovered. Most of the species were discovered in deep sea expeditions off Canada's Atlantic Coast and the Sangihe Talaud Region off Indonesia. I'm going to tell you about the species from the information that MSN gives but I will do some more research on these species at a later date as they intrigue me! If you click on the bold names of the species it will take you to the MSN page with them on. These photos are not mine, they are from the MSN website.

1) A Deep-Sea Chimaera

This image was provided to MSN by the National Oceanic and Atmospheric Administration. Chimaeras share an evolutionary history with sharks and only branched into separate species 400 million years ago. They have mechanoreceptors that detect pressure of the water around them and they use these to navigate in the ocean. These can be seen in the photo, they are the lines on the organism. Ampullae de lorenzini near the mouth can detect electrical fields generated by other organisms. These will also help in navigation and maybe in avoiding predators and detecting prey.

2) Purple Octopus

This Purple Octopus has not been identified according to MSN. It was one of 11 potentially new species that were found in the deep sea expedition off Canada's coast in July of this year. 

3) Strawberry Crab (New Pedal Crab)

This odd looking crab was discovered by a Taiwanese professor named Professor He Pinghe from the National Taiwan Ocean University. He named it the New Pedal Crab (Xin Hua Ban Xie) but the nickname "Strawberry Crab" stuck after people realised it looked just like a strawberry.

4) Miniature Frog (Microhyla nepenthicola)

A new species of miniature frog (Microhyla nepenthicola) was discovered in August of this year and is about the size of a pea. It lives inside and around Pitcher Plants in forests on the island of Borneo. It is part of the Microhylid family which consists of miniature frogs that are under 15mm in size.

5) Sea Star

 This Sea Star is thought to be a new species and was found off the coast of Newfoundland in Canada during a 20-day research trip off Canada's Atlantic coast.

6) Sea Sponge

This odd looking creature was photographed by the National Oceanic and Atmospheric Administration near Indonesia. It is a flower like sponge which is thought to be carnivorous.

7) Unidentified Octopus

This species of Octopus was also found in the expedition off the coast of Newfoundland in Canada and has yet to be identified. 

8) Sea Lily

This photograph of a Sea Lily was taken by the National Oceanic and Atmospheric Administration. The Lily was found 516 metres below the ocean surface in a region off Indonesia

9) Octopus

This photo of an unidentified Octopus was taken by the National Oceanic and Atmospheric Administration. This Octopus was also found off the coast of Indonesia.

Welcome!

Hello, welcome to my Zoology blog! I hope to bring you interesting information and research to do with Zoology. This involves physiology, animal behaviour and ecology as well as other things so stick around!

Billiesue