Cold-Blooded Animals and the Cold
Jane Younger, University of Bath
Curious Kids is a series for children. If you have a question you’d like an expert to answer, send it to curiouskids@theconversation.edu.au You might also like the podcast Imagine This, a co-production between ABC KIDS listen and The Conversation, based on Curious Kids.
How can penguins and polar bears stay warm in the freezing cold waters of Antarctica? – Riley, age 8, Clarksville, Tennessee USA.
Thanks for your question, Riley. The first thing I should probably say is that while a lot of people think polar bears and penguins live together, in fact they live at opposite ends of the Earth. Polar bears live in the northern hemisphere and penguins live in the southern hemisphere.
I’m a penguin researcher so I’m going to explain here how penguins can stay warm in Antarctica.
There are four species of penguins that live in Antarctica: emperors, gentoos, chinstraps, and Adélies.
All these penguins have special adaptations to keep them warm, but emperor penguins might be the most extreme birds in the world. These amazing animals dive up to 500 metres
below the surface of the ocean to catch their prey, withstanding crushing pressures and water temperatures as low as -1.8℃.
But their most incredible feat takes place not in the ocean, but on the sea ice above it.
Emperor penguin chicks must hatch in spring so they can be ready to go to sea during the warmest time of year. For this timing to work, emperors gather in large groups on sea ice to begin their breeding in April, lay their eggs in May, and then the males protect the eggs for four months throughout the harsh Antarctic winter.
It’s dark, windy, and cold. Air temperatures regularly fall below -30℃, and occasionally drop to -60℃ during blizzards. These temperatures could easily kill a human in minutes. But emperor penguins endure it, to give their chicks the best start in life.
Emperor penguins have four layers of overlapping feathers that provide excellent protection from wind, and thick layers of fat that trap heat inside the body.
Have you ever noticed that an emperor penguin’s body looks too big for its head and feet? This is another adaptation to keep them warm.
The first place that you feel cold is your hands and feet, because these parts are furthest from your main body and so lose heat easily.
This is the same for penguins, so they have evolved a small beak, small flippers, and small legs and feet, so that less heat can be lost from these areas.
They also have specially arranged veins and arteries in these body parts, which helps recycle their body warmth. For example, in their nasal passages (inside their noses), blood vessels are arranged so they can regain most of the heat that would be lost by breathing.
Read more:
Curious Kids: Why do sea otters clap?
Male emperor penguins gather close together in big groups called “huddles” to minimise how much of their body surface is exposed to cold air while they are incubating eggs.
This can cut heat loss in half and keep penguins’ core temperature at about 37℃ even while the air outside the huddle is below -30℃.
The biggest huddles ever observed had about 5,000 penguins! Penguins take turns to be on the outer edge of the huddle, protecting those on the inside from the wind.
Incredibly, during this four-month period of egg incubation the male penguins don’t eat anything and must rely on their existing fat stores. This long fast would be impossible unless they worked together.
Emperor penguins are uniquely adapted to their Antarctic home. As temperatures rise and sea ice disappears, emperors will face new challenges. If it becomes too warm they will get heat-stressed, and if the sea ice vanishes they will have nowhere to breed. Sadly, these incredible animals may face extinction in the future. The best thing we can do for emperor penguins is to take action on climate change now.
Read more:
Curious Kids: is water blue or is it just reflecting off the sky?
Hello, curious kids! Have you got a question you’d like an expert to answer? Ask an adult to send your question to curiouskids@theconversation.edu.au Please tell us your name, age and which city you live in. We won’t be able to answer every question but we will do our best.
Jane Younger, Research Fellow, University of Bath
This article is republished from The Conversation under a Creative Commons license. Read the original article.
The link below is to an article that reports on the impact of global warming on cold climate lizards.
For more visit:
http://science.nbcnews.com/_news/2013/03/08/17238399-warming-planet-killing-off-cold-climate-lizards-says-study
The link below is to an article that considers Antarctica’s Emperor Penguins and how they survive the extreme cold.
For more visit:
http://blogs.smithsonianmag.com/science/2013/03/how-emperor-penguins-survive-antarcticas-subzero-cold/
The article below reports on the growing concern over changes in the Antarctic Bottom Water. This is likely to be a result of climate change and global warming.
For more, visit:
http://www.ouramazingplanet.com/2651-coldest-deepest-ocean-water-disappearing.html
I have had a most interesting couple of days on the road and in the bush. Currently I’m in a motel room at Woolgoolga, near Coffs Harbour on the mid-north coast of New South Wales, Australia. ‘Hardly the wild,’ I hear you say, and you’re quite right – it isn’t. The weather was beginning to change I noticed on the final leg of my day’s itinerary, so I decided to hide out in a motel room for the night – good decision, it’s pouring outside.
I won’t give all away – I’ll leave the main description of the holiday to the website – but just some of the ‘downlights’ of the first couple of days for this post.
I didn’t arrive at Cathedral Rock National Park until just on dark, but did get the tent up prior to darkness arriving – when it did, it was dark! The campfire took an eternity to get going as all of the timber was damp and by the time I got it started it was time for bed – all-be-it an early night (7.30pm). I had decided to not spend the money on replacing all of the gear I needed to replace for camping, following the loss of a lot of gear over the years due to storage, etc. I hadn’t done much in the way of bushwalking or camping for years due to injuries sustained in my car crash and a bad ankle injury, so I left it all a bit late. I figured that for this holiday I’d make do and replace the gear with quality gear before the next trip. In short, I’ll get by – but it would have been nice to have some good gear just the same. It was a very cold night let me tell you – and long.
When I reached the heights of my first walk today, standing on top of Cathedral Rock National Park, my digital camera decided to die on me. I knew there was something wrong with it during the ascent as it was really chugging away taking pictures. I did get a couple of reasonable panoramic shots on the top of Cathedral Rock before it died, so that was good. I took stills with the video camera I was using, so it wasn’t a complete loss. When I completed the Woolpack Rocks walk I made the trip to Coffs Harbour to seek a replacement and got one for a reasonable price. It’s just another compact and so I will also buy a digital SLR prior to my next trip I hope. My previous SLR was basically destroyed when the camera cap came off during a multiple day bushwalk and all manner of stuff got into it. It wasn’t digital so I didn’t bother repairing it.
So tomorrow – off to Dorrigo National Park I hope and several lengthy walks I haven’t done before. Hopefully the rain will clear.
I have been doing a little work on the planning side of things for my holiday. There have been some changes and these will be explained below.
Firstly, I have decided to push the holiday back a bit. There are a few public holidays during January 2010, so I think I can cope with a few extra weeks at work before needing the break. So instead of taking the holiday at the start of February, I am thinking of taking the holiday for two weeks in late February – early March 2010, or maybe a week or so later than that.
The later time for the holiday will also allow me to save for the trip and ensure I have everything I want for the holiday. I may even be able to get a digital video camera by then, which will be a great plus.
Secondly, the destination has also changed. I won’t be going out west as temperatures out that way are sure to be very hot and somewhat unbearable for any bushwalks I would want to do. The out west option will need to be looked at for a winter holiday (even though night temperatures are bound to be quite cold then). I do have a plan underway for that option also, which will probably mean a holiday in about August – September 2010 (but that is another story for another time). So to make sense of these two possible (probable) holidays in my Blog posts, the earlier holiday will be called the summer holiday 2010 and the later the winter holiday 2010.
So instead of going way out west for the summer holiday 2010, I’m thinking of going west a little (and to the south), before heading back to the southeast and travelling through the far southeast of New South Wales.
Are there any solid plans? Solid may not be quite the word for it, but I am settling on what I’d call a fairly sure itinerary for the first couple of days of summer holiday 2010. The date is certainly not fixed and that is really quite flexible at the moment. The itinerary for the first few days will probably be:
Day 1 Destination – Dubbo
Day 2 Destination – Conimbla National Park
Day 3 Destination – Wagga Wagga
So the next stage of planning will be to iron out the itinerary for these first three days before moving on towards my planned far southeast New South Wales travels.
For information on Conimbla National Park:
http://www.environment.nsw.gov.au/NationalParks/parkHome.aspx?id=N0053