How many species of animals have been identified to date? The answer is close to two million and they are the most varied living thing on planet Earth. They have struggled to overcome tremendous obstacles, adapting their lifestyles in order to survive. They range from the animals that we all familiar with, big cats and birds of prey to the animals we have never heard of that live on the sea bed.

Animals are usually easy to distinguish from other forms of life because most of them have the ability to move. This rule works very well for most of the animals that live on the land but it is not always the case for those that live in water. Here they live in water and in some cases have trailing arms or tentacles that make them look like plants. A reliable way of identifying animals is by their basic biological features. Their bodies are composed of many cells and they have nerves and muscles that enable them to respond to the world around them. They get the energy that they need by taking in food.

Animals are highly complex and responsive compared to other forms of life. Even the most simplest of animals react quickly to changes around them, shrinking away from potential danger or reaching out for food. The animals that are able to learn from experience and are unique to the animal world, are those animals with well developed nervous systems. The worlds largest living animals, baleen whales can live up to 25 metres long and weigh 120 tons. At the other end of the scale are microscopic organisms and sub microscopic flies and beetles. These animals are so tiny that their weight is negligible but they still possess the body systems that are needed for survival.

Because of their differences in sizes animals can live in different ways. Whales have few natural predators and the same is true of elephants, which is the largest land animal. They are able to process food on a very large scale because of the massive size of their bodies. However they take a long time to reach maturity, which means that they are slow to reproduce. Insects on the other hand are easy prey for many animals and their small size means that their bodies are not as energy efficient as large animals. But because they can breed very quickly when the conditions are in their favour, their numbers can rise at a very fast rate.

Almost all of the world's largest and most familiar animals are vertebrates; these are animals that have backbones. They include the fastest animals on land, sea and air and also the world's most intelligent species (homo sapiens). Vertebrates are all related to each other, sharing a common ancestry that goes back millions of years. However despite the fact that vertebrates lead the animal kingdom in many fields, they only make up a small minority of the animal species known today. Animals without backbones, invertebrates, constitute the vast majority of animal species.

Invertebrates often have very little in common with each other (unlike vertebrates), apart from their lack of a backbone. The giant squid which is the largest invertebrate, can measure over 16 metres long but it is very much an exception. Most of the invertebrates are very small and live in inaccessible habitats.

Most animals are cold blooded (ectothermic), which means that their body temperature is determined by that of their surroundings. The ability to generate their own heat and to maintain a constant internal temperature, regardles of the conditions outside, is particular to warm blooded (endothermic) birds and mammals. This difference in body temperature has some far reaching effects on the ways that animals lead their lives; this is because animal bodies work best when they are warm. Reptiles, amphibians and insects are cold blooded animals. They can exist very easily when the conditions are warm but if the temperature drops, there work rate and energy slows down. They are able to absorb some heat by being out in the sunshine but if the temperature falls below about 50 degrees fahrenheit, their muscles work so slowly that they find it difficult to move. Mammals and birds are hardly affected by this kind of temperature change. Their internal heat and good insulation enable them to remain active even when the temperature falls below freezing.

In a physical way vertebrates function as separate units even though they may live together in families or in larger groups. In the invertebrate world it is not unusual for animals to be permanently linked to together, forming clusters that are known as colonies. These colonies often look and behave like single animals. Most are static but some, particularly those that live in the sea, are able to move around. Colonial species include some of the world's most amazing invertebrates. Pyrosomes, for example, form colonies that are shaped like test tubes which are large enough for a diver to swim enter. However in ecological terms the most important colonial animals are reef building corals, which create complex structures that provide havens for a range of other animals. In reef building corals, the members of each colony are usually identical. But in some colonial species, the members have different shapes that are designed for different tasks. An example of this is the Portuguese man o' war which looks like separate animals, called polyps that capture food, digest it, or reproduce. They use a giant filled polyp as the colony's float and dangle beneath it.

Animals obtain their energy from organic matter or food. They are able to break food up by digesting it and then absorb the substances that are released. These substances go into the animals cells where they are combined with oxygen to release energy. This process is called cellular respiration and is a controlled form of burning, with food acting as the fuel.

The majority of animals are either herbivores who eat only plants, omnivores which eat both plants and other animals and carnivores which eat other animals. There are also scavengers that feed on dead matter. All animals, regardless of their lifestyle ultimately provide food for other animals. All are connected by food chains which pass food and energy to one another. 90 per cent of an animal's energy is used to make its own body work and therefore food chains are rarely more than six links long.


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The Arizona state tree is the Palo Verde. Palo Verde is Spanish for "green pole" or "green stick.", and refers to the tree's greenish branches and trunk. The spelling of the tree's common name varies from "paloverde" to "palo verde", but "palo verde" is the most common.

Arizona became a state in 1912 but the Arizona state tree was officially adopted in 1954, introduced to the Twenty-first Legislature of Arizona by 11 different women residing in six different Arizona counties. It's interesting to note that the legislation that adopted the palo verde tree did not specify a particular variety. The Arizona Revised Statutes, Title 41, Chapter 4.1, Article 5, Section 41-856 is titled "State tree" and simply states that "The Palo Verde (genera cercidium) shall be the state tree."

Two Palo Verde species are native to Arizona. The Cercidium floridum has blue-green branches and leaves, and is commonly referred to as the Blue Palo Verde. The Cercidium microphyllum has yellow-green branches and leaves, and is commonly referred to as the Yellow or Foothill Palo Verde. Both species of palo verde are spiny, multi-trunked, deciduous trees. Yellow palo verde trees reach about 20 feet in height and have more yellowish bark and duller yellow/white flowers. Blue palo verdes, on the other hand, can grow as tall as 40 feet. Their branches and leaves are bluish-green and are larger than the yellow palo verde.

Palo verde trees are flowering trees in Arizona that bloom in the spring. During their short flowering seasons, both species produce thousands of five-petaled yellow blossoms which attract various pollinating insects including bees, beetles, and even flies.

The blue palo verde tree requires the most water of the two species, and is found most often in washes and other areas with higher water availability and finer soil. The yellow palo verde tree requires less water, and is found most often in coarser soils on higher ground away from washes. Yellow palo verdes often live over 100 years and may reach up to 400 years of age, while blue palo verdes grow faster and die sooner, rarely reaching even 100 years.


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We are members of the local Roger Williams Zoo and take some time to visit the zoo when we can. They have a wonderful assortment of animals to see.

Our daughter Emily's favorite animal is the elephants, because their name begins with E.

When we first got to the elephants they were outside and sort of far away in a fenced in area. The zoo is going through some reconstruction. They're expanding the elephant and giraffe (who live next door) exhibit spaces. They'll have a lot more room to roam and a bigger pond to enjoy.

The zoo has an indoor pavilion. Inside we saw the giraffes, which I've gotten to like. The giraffes had a couple of babies this year, which we got to see on our last visit. The baby giraffes have since moved to a zoo in Chicago. The adult giraffes enjoyed the cooler space in the pavilion.

In the elephants area I couldn't help notice one of the walls. It has paint strokes on it. Apparently they give the elephants some painting time. One way they keep them active. One sign described each elephant's individual paint strokes. Imagine, they each painted (if you care to call it painting) in their own way. I thought that was neat. It reminded me of a site I saw in a message where an elephant learned to paint. Apparently it gives the elephants something interesting to do besides the usual routine. Interesting for sure.

Here is a link to an elephant that paints. http://www.elephantart.com/catalog/default.php?cPath=69

Later on during our visit to the zoo, we stopped by the pavilion again. The elephants were in having "lunch". The girls loved them. One can't help but marvel at their size. They're the biggest land animal living on our planet.

Their trunk is amazing too. They can not only breath through it, but can spray water into their mouth or on themselves. They can use their trunk to lift heavy logs or branches. The end of the trunk has a finger like muscle. It can delicately pick up a piece of hay or grass. Just incredible really. Nature holds many wonders and the elephant is sure one of them.

I naturally got some pictures to add to my collection of photos. I'll have to take some time to create some of my own art images of them from the photos.

I'll showcase them here, when I get them done.



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