Frozen in Time

Fossils give evidence about many different ancient life-forms. Bones, footprints, and other signs of animal and plant life can become fossils as their organic components are replaced by mineral compounds. Many arthropods were trapped in the sap of certain trees. When this sticky substance hardened, it became what is called amber. Amber is very useful for studying processes that gave rise to the diversity of life on Earth. •

^^ The color of fossilized amber depends on the type of tree it ^ came from, when it was formed, and the environment where it was fossilized. Amber is usually yellow, although it may come in many shades ranging from orange, red, brown, blue, and green to transparent varieties. Although color is important, amber is classified according to its origin.

Mineral deposit Origin Shades

Baltic

Eocene conifers

9

Burma

Eocene Burseraceans

Dominican Republic

Miocene legumes

m

O

Sicily

Miocene Burseraceans

G

m

Romania

Miocene legumes

Mexico

Miocene legumes

0

Canada

Cretaceous conifers

f/

'-^jS'

Properties and Characteristics

^^ Amber is a material derived from the fossilized resin of ^ certain trees that lived betweenl44 and 65 million years ago. Over time they were fossilized, forming large, irregular masses within layers of sandstone and slate mixed with clay. Masses of amber range from very small, only a fraction of an inch, to many times longer, up to 20 inches (50 cm) in length, with a hardness of 2 to 3 on the Mohs scale. Amber is composed of carbon, oxygen, and hydrogen.

a resinous substance that oozed out in the form of drops.

This su!jf®!jce accumulated on tree branches and bark and at Hfce' foot of the trunk, trapping ai sorts of plants and animals

Ancient fciTe-Forflis

^^ Finding these fossilized craatures enables us to learn ^^ about life-forms and environments of the past. The presence of certain fossils can help us to determine what the climate was like millions of years ago and to date rock layers.' We know that certain plants and animals lived in specific periods. Their presenqiof absence can help us determine the age of the rock lajffjj. where they are found. Not only did amber preserve plants antranimals, but it also trapped air bubbles.

The resin insulated the animal from the an(l

^otected its remains from ™ter and air. As the resin fjr^ened, it gradually formed a protecti«,. pressure-resisl^nt layer. Over time this layer was tr^jsfoTmed into what we krraw today as amber.

The First Conquest

To be able to live on land, invertebrates developed ways of breathing and moving that were adapted to a land environment. Thus insects, which can walk and fly, have populated land and air environments. Other invertebrates have also become accustomed to life in this element, and they play an important role in land ecosystems. •

"Hj

MONARCH BUTTERFLY

Danaus plexippus rk m 'l Jfitij tfwf-vv ■ J*..-«-iL'

Who Eats Whom?

The relationships of eating and being eaten that are established among the organisms of an ecosystem are called the food chain. In contrast to plants, whose capacity for photosynthesis gives them the role of food producers, invertebrates occupy various levels in the food chain as food consumers.

THE ORDER OF THE FOOD CHAIN

Fleas

Spiders

I FIRST LEVEL

Invertebrates that eat plants

"I SECOND LEVEL

Carnivores that eat herbivorous invertebrates

Spiders

3! THIRD LEVEL

Larger invertebrates that eat other carnivorous invertebrates

OF THE SPECIES THAT .- ■■ . LIVE IN TREES ARE INSECTS.

PRAYING MANTIS

Family Mantidae

ASIAN TIGER MOSQUITO

Aedes albopictus

CRAMER'S BLUE MORPHO

Morpho rhetenor

PRAYING MANTIS

Family Mantidae

CRAMER'S BLUE MORPHO

Morpho rhetenor

The Most Successful

Beetles (order Coleoptera) are the most prolific and diverse group of the animal kingdom. This is mostly because of their chitinous exoskeletons and highly compact elytras (wing covers), which give each species the hardness, flexibility, texture, or color it needs to adapt to its environment.

OVER

350,000

SPECIES OF BEETLE

ARE KNOWN.

MMON Tunnels bored

FURNITURE BEETLE by beetles Anobium punctatum

FEEDING ON

TICK

Boophilus s p.

BURYING -

BEETLE

EUROPEAN HORNET

BROWN Vespa crabro

GARDEN SNAIL

GARDEN SNAIL

Helix aspersa

BLACK VINE WEEVIL

Otiorhynchus sulcatus

SILVERFISH

Lepisma saccharina

Small Arthropods

Most land- and air-dwelling arthropods have a tracheal respiratory system consisting of highly efficient air tubes that supply oxygen directly to the cells and tissues. The tracheal system makes it possible for these arthropods to maintain a high metabolic rate, but it also tends to limit body size. That is why land-dwelling arthropods are relatively small compared to the rest of the animal kingdom.

DESERT MILLIPEDE

Orthoporus ornatus

SPIDER

Drassodes sp.

CENTIPEDE

Lithobius sp.

PILLBUGS

Armadillium sp

CLICK BEETLE

Agriotes lineatus

SILKWORM

Bombyx mori

EARTHWORM

Lumbricus sp.

BLOOD-RED ANT (WORKER)

Formica sanguinea

Naturally Programmed

The world of air- and land-dwelling invertebrates includes societies, such as those of bees, wasps, and ants (order Hymenoptera). The bees' dances to inform other bees about the location of new food sources, their strict division of labor, or the structure of a spiderweb correspond to patterns of behavior specific to each species. Each individual carries these patterns inscribed within, like a computer program that executes perfectly.

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