How did you do with this week’s Mystery Creature? This charming moth is called a “Buff tip” (Phalera bucephala).
Image Credit: Michael Bell (Nature Learn)
Image Credit: Michael Bell (Nature Learn)
As most moths are nocturnal they need to rely on good hiding areas or camouflage to survive during the day. The Buff tip is a true master in the art of camouflage. Not only does its colour and markings blend in among the branches of the trees upon which it rests but its body shape is also ideal to make it look just like a twig.
These moths are fairly common in Ireland and throughout Europe. They have a wing span of between 4 and 7 cm. The Buff -tip over winters in the crysalis state underground, emerging in adult form in early Summer. The female lays large groups of eggs which hatch en-masse. The black and yellow larvae tend to feed in large groups after hatching, moving towards a more solitary lifestyle as they grow. They feed on a variety of deciduous trees such as birch, hazel, alder and oak. In the Autumn they pupate underground and the cycle begins again.
These images (unless otherwise stated) were kindly provided by Michael of Nature Learn, a Nature Education program for schools and public groups. Keep watching for another Mystery Creature from Nature Learn in the coming weeks!
Clouds are made up of tiny drops of water or ice crystals. They form when warm air picks up water vapour from the land or sea and carries it into the sky turning it into water droplets or ice crystals!
The study of clouds is called Nephology.
Let’s learn more!
There are lots of ways to describe clouds but they are usually named based on their height in the sky, their shape or the weather they can bring!
If a cloud name starts with “cirr-” then you know it must form very high in the sky (over 20,000 feet).
If a cloud name has “Alto”- in it then it is in the middle section of the sky (between 6,500 and 20,000 feet).
Clouds with “Strato-” in the name are found in the lowest part of the sky (below 6,500 feet).
The clouds that are really high in the sky are mainly made up of ice crystals as the air is so cold.
Clouds at ground level are called “fog”.
Did you know…all clouds are white but can appear grey or dark when seen from below? This may be due to the amount of water they contain and shadowing by clouds above them.
Clouds named according to their shape will contain one of these Latin words in their name…
Clouds called Cumulonimbus are often referred to as thunder clouds as they usually bring thunder storms!
Cumulonimbus clouds are the tallest of all the clouds.
Cumulonimbus looks a bit like a giant cauliflower in the sky!
Did you know… a sinlge cloud can hold billions of pounds of water?
Clouds are carried along by the wind and can often travel quite fast;
Thunder clouds (Cumulonimbus) usually travel about 64 kilometres per hour (kph). The highest clouds (above 20,000 feet) can reach speeds of over 160 kph!
An experiment to try at home:
Make a cloud in a bottle!
You will need… an empty 2 Litre plastic bottle, warm water and a match.
What to do… Fill the plastic bottle one third full with warm water. Put the cap back on and squeeze and then release the bottle. Nothing happens. Ask an adult to light the match and put it into the bottle. Replace the cap quickly. Try squeezing and releasing the bottle again. What happens this time?
So what is happening?…Once the match has been added to the bottle a cloud forms when you squeeze and then release the bottle (if you squeeze again the cloud dissapears and reappears when you release). To make a cloud you need water vapour, small particles (like the smoke) and a decrease in air pressure.
Our garden is bursting with life at the moment! Busy, haggard birds are flitting around, building nest and laying eggs. Insect populations are slowly emerging and even our hens are getting broody! For the first year ever we have a number of young rabbits joining in the ecosystem that is our back garden. The rabbits in particular have attracted the children’s attention. You can understand why… there must be at least five of them and they are very tiny, very cute and very independent! That got my children wondering….
…”WHY ARE THEY OUT WITHOUT THEIR MAMMY?”
THE RABBIT’S MOVE TO INDEPENDENCE
Rabbits are independent from a very early age. A female rabbit (called a Doe) will give birth to a litter of four to twelve baby rabbits (called Kits). The kits are born blind and without any fur. However within a week their eyes have opened, their fur begins to grow and their ears begin to stand upright. Wild rabbits will begin to wean about two weeks old and within three weeks they have grown enough to leave the nest and live independently. They may look small and helpless in our back garden but they are old enough to go it alone in the wild.
A doe can reach sexual maturity between three and six months and can live for up to ten years. The breeding season of rabbits usually last three quarters of the year. The most amazing aspect of the rabbit though, is that fact that the doe has no oestrus cycle. She can literally get pregnant a day after giving birth. Her gestation period is only one months long.
If you want to do the maths on all that it means that one doe could give birth to up 80 to 100 kits a year, or as many as 1,000 kits in one lifetime. With these turnover rates you can see why the kits have to be independent pretty quickly!
WHAT ABOUT BIRDS?
The busiest members of the garden seem to be the birds. Nest building, egg laying and then feeding a brood of hungry and demanding chicks. For the first part of their lives these chicks are completely dependent on their parents for food and the parents spend the early summer months on a non stop conveyor belt of foraging and feeding. The chicks learn to out “beg” their siblings rather than how to feed themselves. Of course this does not last for long, eventually these young birds will learn to fly and forage all by themselves … no mean feat!
Why do birds choose to feed rather than encourage foraging at an earlier stage? By evolving in this manner birds can choose to build their nests in more isolated, out of reach places, such as high up trees or on cliff edges. The compromise is that such places do not have a ready supply of food so the parents must go and source the food and bring it back. Although an exhausting process, the chicks are more likely to survive!
WHAT ABOUT THE INSECTS AND THEIR YOUNG?
This one depends on the insect obviously. Most insects’ parenting work ends with the lay of their eggs. This they usually do in large quantities, to increase the chances of survival of at least some of their progeny. Once the young hatch they are on their own! Often having to work their way through a number of different forms and changes before they even make it to adulthood! Imagine what it must be like to morph from a grub to an adult? Must be like going through your teens without any parental guidance what so ever!
Not all insects leave their young to their own devices of course. Some bee, wasp and ant species tend to the eggs in colonies of nests or hives. Once the larvae emerge from the egg they are fend and tended to completely, passing through different developmental stages until they pupate and emerge as adults.
HOW DO HUMAN INFANTS COMPARE?
The insects and birds mentioned above rely on their young doing most of their development outside the adult body, in eggs and/or larval stage. They are not mammals (giving birth to live young) like rabbits or humans. We have seen how quickly the rabbit young develop and gain independence from their mother. This is not the case with human infants though. So why the big difference between the dependence of the young in rabbits and humans?
Factors that influence the level of dependence of young on the adult can include…
size of the fetus
size of the mother
number of young per birth
brain size and growth rate
cultural behaviour of the species
Rabbit have large litters, short gestation periods, a less developed brain and a shorter life span than humans. These facts all explain the difference in dependence of young.
If we look at all mammals we find that humans have very dependent young relative to most other species.It is thought that our evolution into bipedal (walks on two legs) creatures has meant that our young must be born with smaller brains and that the brain develops more after birth. This is for physical reasons: in order to walk upright the size of our pelvis is restricted and therefore the size of the infants we give birth to is restricted.
To examine infant dependence even further we can compare the dependence of human young with those of other primates; Human infants are much more underdeveloped at birth than their primate relatives! In fact human development is thought to take 30% to 50% longer than that of other primates. Why is this the case? Perhaps it goes back to the point that life span may play a role in infant dependence? This point alone does not account for the big difference observed between humans and other primates. Other suggestion that might contribute are the nutritional demands on the mother during gestation and the amount of growth and development the brain will undergo after birth.
Scientists are now also looking at the contribution of maternal nurture and the cultural development of the society of the species. Humans have evolved a highly developed social and cultural environment. We have developed complex communication methods (e.g. language and social ques) and cultural interactions. In order to fit into such a complex system, perhaps the human infant must learn by observation and inclusion… neither of which it can do in the womb. Maybe we are born with such underdeveloped brains because most of our development and learning can only be done in the culture within which we will live!
…and the adult moth is the SPOTTED HAWK MOTH (Manduca sexta), also known as the SPHINX MOTH.
The adult moth (image source: wiki commons)
This species is very common in America (and probably only present in Ireland as imports). Horworm caterpillars can grow up to three inches in length. The tobacco hornworm is often confused with the tomato hornworm (Manduca quinquemaculata) as both look very similar and can each feed on similar plants. The tobacco hornworm has white stripes along it’s body and a red “horn” while the tomato hornworm has V-shaped markings and a black “horn”.
Horworm eggs are typically laid on the underside of leaves. When the caterpillar emerge they will eat through a large amount of leaves for a month or so before pupating in the soil, building a small hole a few inches below the surface. The adult moths, commonly known as shinx, hawk or “hummingbird” moths emerge from the ground and feed on nectar. The life cycle can be competed in 30 to 50 days and under the right temperatures, there can be two hatches in one Summer.