Making real science accessible and interesting for all people.
Friday, September 28, 2012
Creosote Bush
The Creosote Bush (Larrea Tridentata) is a relentless desert plant growing in the deserts in both North and South America. In North America it is found in the hot Mojave, Sonoran, and Chihuahuan Deserts where it is possibly out numbers all other perennial plants. The only North American desert where it is not found is the Great Basin, simply because it is too cold. The Creosote is so relentless it can occupy the poorest soils in flat basin areas between the mountain ranges of these deserts. Driving through the flat lands of these deserts you can drive mile after mile past near mono-cultures of this plant. Its roots are so effective at extracting moisture from the soil that it is often very difficult for other plants to become established near Creosote. Creosote roots can extract water from soil that is seemingly dry, surviving up to two years without rainfall. They can also extract nearly all water from the soil, thus preventing any from ever reaching the water table. Creosotes are so good at all this that they can in-fact survive for over 11,000 years!
Monday, September 24, 2012
Bringing back the Wooly Mammoth
The last known population of Wooly Mammoths went extinct about 4,000 years ago. The last population existed on Wrangel Island off the coast of Siberia. Wooly Mammoths were extremely elephant like in both size and shape. The big differences though between the two lies in their adaptation to climate. Modern day elephants are adapted to the tropics. Wooly Mammoths had fur similar to yaks and a thick layer of fat to help hold in heat. Mammoths also had smaller ears which helped them hold heat in better. These adaptations are of course why the mammoth lived in the icy tundra and thrived during the ice age. As the world warmed, bringing the ice age to an end, suitable habitat and areas of food shrunk significantly for the mammoth. The warming climate along with increased human hunting pressure at the end of the ice age led to the extinction of this huge mammal.
Even though the mammoth has been extinct for 4,000 years now, scientists are working to clone one back to life again. The process is simple in theory. Scientists must first find a living mammoth cell and extract the nucleus. The nucleus of a modern day elephant embryo must be removed and replaced with the mammoth nucleus. Then, this embryo must be impregnated into an elephant mother. If the embryo survives, a baby mammoth will be born to the mother elephant. All of these processes are well known and have been successfully carried out, but never for wooly mammoths. In practice however, this process appears nearly impossible. The first step of finding living mammoth cells is what makes this so difficult. But once living cells are found, the rest of the process would be relatively simple.
The preference of mammoths for icy cold habitats is what makes this entire process possible in theory. As mammoths died in the frozen tundra, there is the very likely possibility their bodies would have frozen very quickly, thus preserving living cells in a frozen state. Indeed, many frozen specimens of ancient mammoths have been found. Not a single living cell in these frozen specimens has been found though and the probability of a cell surviving thousands of years even in a frozen state isn't very high. It is still possible though. And just the fact that it is possible makes at least a few people want to try. Just think how awesome it would be to go visit a living wooly mammoth at the zoo. Or see a wooly mammoth performance when the circus comes to town. OK, that's sort of silly but just think...
Friday, September 21, 2012
Post Summer 2012 Sonoran Desert Monsoon Season Photos
The high humidity and rain from monsoon season seems to be gone from the Sonoran Desert this year. There is always a chance that it can come back, but as far as monsoon seasons go, this year was a good one. The vast majority of the Sonoran Desert received more than the normal amount of rain and cooler than normal temperatures over a two and a half month period. This had a great effect on greening the desert, wildflower blooms, an explosion in bugs, and increased wildlife activity and reproductive success. Below I have shared a number of photos I took on a recent hiking trip the day after the last rainstorm we received.
A leafed out ocotillo. |
Not sure what this catapillar is but I found thousands of these along the trail. |
Butterflies are quite abundant now as a result of the rains. |
Viguiera |
A green desert grassland of Tobosa located near the top of the White Tank Mountains. |
Trailing four o'clock |
Monday, September 17, 2012
Ocean Acidification
Ocean acidification is becoming a serious issue today. Within the next hundred years it will become extremely serious. Since the industrial revolution the oceans have been absorbing huge amounts of carbon dioxide due to the burning of fossil fuels. As the oceans absorb this carbon dioxide it is converted into carbonic acid. Oceans have already dropped 0.1 in pH and are predicted to drop another 0.3 to 0.5 in pH within the next 100 years. These drops in pH might not seem like much but in reality are over a 100 percent increase in acidity. This increase will have extreme consequences for shell forming organisms. As acidity increases, the calcium in shells increasingly dissolve. This can kill the organism or cause it to work harder to develop its shell. Corral reef also will have increasingly difficult times forming as acidity increases. In-fact, many people predict all corral reefs will be gone by the year 2050, which means a mass extinction of organisms that are completely dependent on corrals. As shell bearing organisms disappear, organisms higher up the food chain also will disappear along with there food sources. No one really know what exactly is going to happen, but everyone agrees it will not be good. Fortunately, the solution to this problem is within reach. To prevent continued acidification we must stop the mass burning of fossil fuels and switch to sustainable energy sources such as wind and solar. Only with this switch can we decrease the increase in carbon dioxide and therefore stop global warming as well as ocean acidification. Below is a documentary that aired on Discovery Planet Green that does an excellent job covering this topic.
Friday, September 14, 2012
Everyone Should Love Garlic
Garlic is one of the worlds oldest cultivated crops. 6,000 years ago it was originally cultivated in central Asia. From there it spread through out the world and has been a common staple or spice in cultures everywhere. The ease at which garlic grows in a wide variety of environments throughout the world, along with the amazing number of aliments it has been used to treat, are very likely reasons for its spread throughout the world. Since ancient times, physicians have been prescribing garlic as a remedy for all kinds of health problems. With many ancient remedies, science has not been able to identify whether or not they work. Often they do not work. Garlic however has a wealth of scientific research to support its many health benefits. Garlic is full of nutrients that help boost the health of the body. Garlic is also loaded with all kinds of chemicals that have been shown to have positive health effects. Many of these chemicals contain sulfur and are responsible for garlic's distinct odor.
One of the most common and most known sulfur containing compounds in garlic is allicin. Allicin is produced by garlic cloves once they are damaged, such as by cutting, chewing, crushing, and so on. Once produced, allicin functions as a strong antibiotic and antifungal. For this reason, many ancient cultures used garlic as an antiseptic, and of course, it still functions as an antiseptic today, albeit a smelly one. Once cooked or as it passes through the digestive tract allicin begins to break-down into extremely strong antioxidants. These antioxidants have been shown to help prevent cancer as well as slow its growth. Other compounds in garlic have also been shown to have healthy effects on the cardiovascular system. These benefits include thinning the blood and lowering blood pressure. All of this points us towards including garlic as a regular everyday part of a healthy diet!
Monday, September 10, 2012
Monsoon Season: Breaking the Desert Drought
About two months ago I posted on how a 4th of July storm broke a severe drought we had been experiencing throughout all of 2012 (Monsoon Season and the Drought). As always with desert rain patterns though, you never know if the rain is going to keep coming or if a single rainfall event was just a fluke. Fortunately, we have had a pretty good monsoon season that began with an earlier than normal large rainfall event and still seems to be going. As of now, most of the desert surrounding Phoenix has received about three inches of rain in the past two months, which is slightly above average. As a result of the rain and additional humidity, temperatures have actually been cooler than normal. We of course have had our 110 degree plus days, but nothing like what we have had the past several years.
The effects of rainfall on the desert over the past two months has been quite dramatic. The drought had been so severe that mesquites and acacias had gone leafless which is fairly rare. Ironwoods also were loosing many leaves and yellowing, which is extremely rare. Other plants such as wolfberry and palo verdes were also leafless. Creosotes were loosing leaves quickly and leaves that did remain were often brown or yellowish. Nearly all triangle leaf bursage looked as if it were completely dead and often brittle bush was just a bush of white crispy sticks. As you looked out across the desert in late June it appeared to be a crispy brown landscape without much life. The rain however changed all this very quickly. Within days of the first rain, new bright green leaves began to sprout. The sustained rain allowed for these leaves to keep growing and for new stems to begin growing also. Creosotes show this dramatic change quite well. Creosotes still retain some of the old more brownish leaves from the drought period. Directly above these brown leaves though bright green leaves are growing like crazy. Ironwoods, palo verdes, wolfberries, mesquites, and acacias are also all full of leaves. One thing I love about the desert after rain is all the different shades of green that color the landscape. Each one of these plants has a slightly different shade, from the dark thick green of the ironwood, to the yellowish light green of the palo verde. There also has been enough rain for the wolfberries and creosotes to flower. Many wolfberries are in-fact loaded with fruit right now as a result of the rain.
All of this has had very positive effects on the wildlife. I have noticed good populations of gambles quail as well as some healthy rabbit populations. I am also sure many of the song birds are benefiting by the increase in berries and bugs. The additional water and grass growth should also be having a positive effect on mule deer, hopefully increasing fawn survival.
So for now, the drought has been broken and with continued rainfall we can hopefully keep from returning back to drought conditions. As of now, the National Weather Service is predicting the return of El Nino this fall and winter, which often means more rainfall. A lot of weather scientists hold La Nina responsible for the drought in the Southwest over the last few years.
Friday, September 7, 2012
Life of a Maple Part 5: Maple Incline and Decline
Healthy sugar maple forest. |
Fire however, strongly works against the maple tree. Remembering back to previous installments of this series on maple trees, you might remember that maples prefer very stable, undisturbed habitats. Anytime fire comes around one of these habitats where maples have become established, the maples are killed off. As a result, prior to European settlement of the eastern deciduous forest oaks, a fire adapted species were far more abundant, and maples, a fire intolerant species were far less abundant. By some estimates in some locations there may be up to three times more maples today than there was in the 1800's. The increase of maples over the last century is a result of fire suppression by European settlers. It was only on the best soils, in the most ideal habitats where fire didn't touch that maples were found in the 1800's and prior.
Sugar Maples in fall. |
Maples moving into areas of less than ideal soil wasn't the best thing for the forest. Being maples are extremely picky about their environment, living in these less than ideal soils made them especially sensitive to drought. Oaks are adapted to drought but maples are not. Maples ideally overcome drought simply by living in the best soils in the forest. But in less than ideal soils, the maples were damaged during drought. The damage did not end with drought though. Drought damage made the tree more susceptible to other problems such as fungal infections and insect damage which often end up killing the tree. So the incline of maples was a direct result of fire suppression allowing maples to move into marginal habitats. Maple decline is a result of maples living in these marginal habitats.
Forest where many of the maple trees are dying due to "maple decline". |
Monday, September 3, 2012
Life of a Maple Part 4: Maple Syrup
If the Sugar Maple tree is famous for anything, it is famous for maple syrup. Early each spring as the snow melts, maple syrup farms spring to life from the Midwest U.S., Northeast U.S., and Southeast Canada. I personally have payed a few visits to these farms and they are always quite an interesting experience. The weather is typically beautiful with temperatures between 30 and 50 degrees. This is at least beautiful compared to the previous winter months. Snow is typically on the ground but melting, which is producing the next most memorable thing about most maple syrup farms: mud. The farms I've visited are always unbelievably muddy. They are so muddy in-fact that horses are often used to gather sap. Horses are used rather than tractors or other vehicles simply because they don't get stuck in the mud!
The story of how maple syrup is made begins with the previous late summer. Late in the summer, the maple tree stops growing and instead stores energy in the form of starch. This starch is stored in the trees sapwood through the winter. Come spring when sapwood temperatures reach about 40 degrees the starch is converted to sugar by an enzyme and moves out of the wood and into the tree sap. Rising temperatures, particularly in the morning as the sun comes up, cause the sap to rise through vessels. The sap rises towards the trees twigs and branches where the sugar will help the tree to begin flowering and budding.
A large maple tree with two taps and buckets for collecting sap. |
Maple syrup was first discovered by and utilized by Native Americans. Europeans quickly picked-up on the practice and refined it to the practice we see today.
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