1 - Overview
2 - Introduction to the area
3 - Geology & Climate
Granite
Climate
4 - Vegetation
5 - Forest Types
Vegetation
Tea/Miang Plantations
Forrest Conservation
6 - The Pang Soong Treewalk
7 - Treespecies
Fig Trees
Epiphytes
Saprophytes
Bamboo
Click here for full tree list
8 - Forest Fires

9 - Birds
Observing Birds
10 - Bird Trail Walk
11 - Mammals
Mammals of Northern Thailand
Mammals of Pang Soong
12 - Insects
Introduction
13 - Projects
Observing Birds & Mammals
Watching Birds, makung use of Observations
Identification
Behaviour
Mammals
14 - Biographies of contributing experts

Ephemeroptera
Besides their numbers and curiosity insects affect the worlds affairs. From the beginning of humankind insects have influenced the aptnesses of man. Since ancient times migratory and Desert Locusts (Schistocerca gregaria and Locusta migratoria) have been occurring as biblical plagues in Africa and ravage the laboriously nursed field crops. Some Egyptian empires may have stumbled over a famine caused by insect pests. Nowadays insect pests like the Desert Locust are still a major threat for agricultural production. According to the FAOSTAT (FAO statistical database) the world applied 86,764 Mt insecticides in 2001 to fight insect pests. This business is of high economic value. 2003 the worldwide import of insecticides reached a total amount of 2,717,360,000 US$. But insects are not always the enemies of mankind. Apart from all the technically inventions of the 20th century agriculture is based on biological processes. A massive number of beneficial insects are holding key positions in cropping systems and assist us as pollinators, bioturbants and parasites of pests. The parasitic wasps of the genus Trichograma are the world famous predator of various insect pests. This wasps are distributed worldwide and around 100 species are recorded. The larvae of Trichogramma evanescens is known to be a freeloader of eggs of around 150 pest hosts. One may argue that these free natural services provided by insects could be replaced by technical approaches. Considering the acquired resource input such an approach would exceed the affordable threshold of every economy. In fact, without the assiduous work of honeybees (Apis mellifica) there would have been little chance for historical cultures to sweeten the normal course of life and today people still appreciate honey as a natural sweetener. Unfortunately, this delicious tidbit has its price.

If you like more, then stick to next pages. You will discover the world of creepy crawlies! First you will roughly introduced into basic classification of Arthropoda. The next chapter will guide you through the aeons of insect evolution and we will address the question: why are their so many of them? Next we present a short excursion into insect anatomy and physiology. You are also free to skip all this information and enter directly the highlight of our story. Explore the world of insects, their struggle of life, their fight against the odds and their fantastic adaption to various habitats.

Insect evolution in general

Enjoying the walk you might question yourself: where did all these insects come from? How did they evolve their shape? Why are they so successful? Well, here are some considerable answers. It is reasonable to believe that the insect ancestor was living in fresh water in the early time. Their life style was similar to the dragonfly larvae except their adult stage was not winged and they find their partners and mate in the water. When insects took their first step on land this happened most likely at the shores of a small fresh water lake or swamp. Some features of modern insects were developed before their landing: like molding. Like their close relatives, spiders and crabs, insects have a stiff exoskeleton. That hard skin gives their body support, but also hinders the growth. Between each stage of growing, insects molt, leave their old smaller size skin, expanse and re-grow a bigger size skin. The feature of molting and re-grow evolved the important feature of insects – metamorphosis, which more differentiated form like in butterflies, can only function on land.

The first important step in the evolution of insects was the development of definite body plan, i.e., the three body parts - head, thorax and abdomen, as described above. This happened approximately 300-350 million years ago Devonian period. This evolutionary step led to the first insect that looked something like silverfish nowadays. These earliest insect species were probably detritivores, scavenging for organic matter in the thin soils of this time, although some species may have been herbivores feeding on live plants.
Most insects fly. One of the pre-required conditions for flying is that there must be a good navigation system, such as a pair of eyes with good eye sight. One of the very earliest identifying features of insects is the compound eye, found only among the insects and some other arthropods. The early primitive winged insects look not too much different from dragonflies today. Also dragonflies cannot fold their wings away, which is assumed to be a primitive characteristic, but to someone who has seen their fantastic flight abilities, they do not seem to be primitive at all.
Approximately 200-350 million years ago during lower Carboniferous, insects developed wings and the ability to fly. These wings were primitive and could not be folded away. The Caboniferous period also saw the largest insects ever evolved on this planet: Meganuera monyi - a giant dragonfly with a wingspan of 60 to 75 cm. By the end of the Carboniferous, the insects had evolved into a large number of distinct orders, including many dragonfly-like forms.
Insects were then dominant in Carboniferous and Permian. All winged insects posses two pairs of wings (or their modificated remnants), which are principally following the same structure, at the same two segments: the meso- and metathorax, while the first throrax segment does never carry wings. The possession of the same number of wings in the same position lead to the assumption that wings have only developed once in insects.

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