Tuesday, July 7, 2009
Thursday, May 21, 2009
Wednesday, May 20, 2009
National Geographic has created an emergency fund to help avert a potential conservation disaster: the complete loss of lions in and around Amboseli National Park, one of Kenya’s most important tourist destinations. As they teeter on the brink of extinction, these lions do not have the luxury of time. The decline in the lion population in this region has reached a critical status that needs addressing on a major scale.
In partnership with Explorers-in-Residence Beverly and Dereck Joubert, filmmakers and conservationists who have worked in some of Africa’s most remote wildlife areas for more than 25 years, National Geographic is committed to this urgent conservation issue. In addition to the fund, National Geographic is providing an emergency $150,000 grant to the Maasailand Preservation Trust, co-led by Richard Bonham and Tom Hill. The grant will aid the trust’s Predator Compensation Fund, which provides compensation to local Maasai herdsmen for livestock killed by lions in and around Amboseli National Park.
animals and insects
Why most animals are insects
Points covered:
- Why are most animals insects?
- How did insects evolve to live on land?
- What is the evolutionary importance of being able to fly?
- What is the importance of the co-evolution of insects and plants?
Words to know:
- EPICUTICLE - the outermost layer of insects' exoskeleton.
- ARTHROPOD - the name for animals with jointed legs and an exoskeleton.
- TERRESTRIAL - pertaining to or living on land.
- SPECIATION - the process of evolving new species.
- IMPERMEABLE - water can't pass through.
- DEVONIAN PERIOD - approximately 410 - 362 million years ago.
Teddy bear bee Amegilla bombiformis. Photo: Australian Native Bee Research Centre
Insects comprise 75% of all animal species that scientists have named and described, and most of these insects have wings. The key to insect success is their ability to survive on land and take to the air.
Insects have adapted well to the terrestrial environment, which demands that an organism must prevent excessive water loss from its body. Insects solved this problem by modifying many aspects of their structure, physiology and habits. For example, the exoskeleton of insects has a special outer layer, the epicuticle, which is impermeable. Also, insects evolved unique solutions to the pressures of breathing, excreting waste without losing too much water and moving about on land.
The evolution of wings is an obvious key to insect success and diversity because it means that most insects can disperse widely and escape unfavourable environmental changes. Flight also provides a means of escaping predators and allows insects to colonise new environments where they may exploit new food sources.
Fossils show that insects were among the first animals to invade land during the Devonian Period, about 400 million years ago. This permitted them to utilise food resources that had not previously been consumed, such as terrestrial plants. The co-evolution of insects and plants has been very important in the histories of both groups. For example, insect mouthparts have evolved specialisations for different styles of biting and sucking plant tissues. Also, the pollination of flowering plants by insects has led to fresh avenues for the speciation of plants.
SES performed by online degree promotion team.
