Desert Lifestyle
The desert is a place in which temperatures range from 40*C to 45*C in the summer time and then at nights they can range all the way from 0*C to -2*C. The precipitation in the desert is less then 50cm a year. This climate and precipitation levels result in no vegetation or very low amounts if anything which can grow in the desert. Organisms living in the desert are very adapted to it through thousands of years of evolution and natural selection. Rattle Snakes, Cactus, Scorpions, and camels are amongst other organisms that inhabit the desert in spite of its harsh climate.
Background
It is believed through fossil records and other evidences that the cactus evolved from other plants 50 million years ago in the Cenozoic age. These plants were believed to have 7 characterized points of a cacti they had thorns just like the Cactus. These plants were made or evolved in times of great droughts that swiped the landscape 50 million years ago. Although there's more organisms and plants that the cactus could have evolved from since the Cenozoic age or earlier it cannot be fully proven and they are just assumptions.
Characteristics and Facts
The cactus is part of the plant family Cactaceae. The Cactus can be recognized as being a plant full of thorn. The cactus ranges from the sizes between large and small. The Cactus's habitat was a very dry place like the deserts of Africa.
- There's about 2000 species of Cacti
- No matter how small the cactus the roots of it were long and sucked deep in the ground
- Cactus spines can be used for sutures after being sterilized by the hot coal
Adaptation
The Adaptations in the cactus from the normal plants that we see everyday is obvious the Cactus has thorns and the plants we see everyday have leaves. The reason of this difference is that the habitat of the cactus is the desert while a plant with leaves has humid and fair climates. The thorns on a cactus are there to reduce transpiration this means less water is lost. water conservation in the desert climate is very important the thorns on the cactus help it do just that. As the climate would get warmer and warmer the plants with leaves had a huge disadvantage in the desert there was some plant with thorns (the cactus) which found it easier to conserve water in the desert and this may have been a genetic mutation but it was favourable as it increased the chances of survival for the plant (the cactus) and therefor slowly more and more plants got it and had thorns and that is how cactus's have thorns today.
The thorns on a cactus also give one more advantage although that is just extra and obvious it provides protection to the cactus from other predators that may want to eat it or gain water from it.
The thorns on a cactus also give one more advantage although that is just extra and obvious it provides protection to the cactus from other predators that may want to eat it or gain water from it.
Evolution (4-points of evolution)
Variations
The Variation is whether the plant (Cactus) has thorns or leaves.
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Struggle
The struggle is that in the Cenozoic climates started getting hotter and hotter and water became scarce the struggle between the cactus is which cactus can get the most water and conserve it.
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Environmental Selection
The environment selected the Cactus with thorns because as explained in the adaptations column the thorns helped reduce water loss in cellular respiration in the cactus while the leaves resulted in the water loss and because the fight was for the water the cactus with thorns had a higher chance of survival and passing on their genetic information then the cactus with leaves and because of this the environment selected the cactus with thorns.
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Reproduction And Inheritance
As the cactus with the thorns lived longer and had better chances of surviving the hot climates and passing on their genetic information more and more cactus with the thorns were seen and more and more were produced as the ones with leaves died off and as more and more cactus with the thorns became prominent the gene that gave thorns in a cactus was passed down from generation to generation until all cactus's were ones with thorn and the ones with leaves had died off.
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Morphological Adaptation
The thorns on a cactus is a type of physical characteristic and therefore it is recognized as a morphological adaptation.