Rocky Shore

The rocky shore biome is a fascinating ecosystems that is packed with a wide variety of marine organisms. During high tide in the intertidal zone the shore is engulfed by sea water and pounded by reoccurring waves, conversely during low tides the shore is exposed to dry heat and air. Plants and animals that thrive in this biome have adapted in such ways to cope against freshwater and saline water, as well as maintaining body water during dry periods and withstanding high salinity when submerged underwater. Animals in this biome are categorized as mobile animals or sedentary animals. Mobile animals are very active moving along with the tides, they can retreat into gulleys and under rocks when faced with stressful environments. Mobile animals include crabs, small fishes, and sea lice. Sedentary animals on the other hand survive best in narrow range condition to which they are adapted, they spend their lives attached to rocks preventing them from being washed away by waves, gaining most of their nutrients from filtration of small particles found in water.

In this investigation the abiotic and biotic factors of the rocky shores were measured using the line transect technique, and prior to setting up the transect the shore was throughly surveyed for it's geographical features. The abiotic factors that were collected included temperature, wave frequency, wind direction, aspect, and light intensity. After the abiotic factors were collected seven quadrats were placed along the line transect and the biotic factors of each quadrat was collected. The collected biotic factor include crabs, periwinkle, barnacles, and knobbed snails, and the distribution of these organisms could be greatly impacted by human disturbances including a pathway built on the rocky shore, as well as a few visible fishing boats docked in the vicinity.

Table 1: Abiotic Factors Rocky Shore (Green Turtle)

Graph 1: Biotic Factors Rocky Shore (Green Turtles)

The abundance of each organism was modeled using the kite diagram. In this part of the investigation seven quadrat was laid down the line transect facing the rocky shore. According to this data there was a abundance in sedentary animals such as barnacles, periwinkles, and knobbed snails, which heavily populate the rocky shore, conversely there is a scarcity in motile animals such as the crab. The explanation for this distribution is because sedentary animals are stationary and exposed to predator with minimum protection, therefore more offsprings are produced during reproduction to ensure survival of the particular organism. On the other hand there is a scarcity in motile animals because they relie on factors such as evasiveness and camouflage hide from predator, so it is harder to detect these organisms. In conclusion the distribution of organism in the rocky shore vary greatly and could be explained using both abiotic and biotic factors.

Mangrove Biome

Mangroves biomes are found in tropical and subtropical tidal areas, which includes estuaries and marine shorelines. There are about 110 species of mangroves that grows in saline swamps, and to overcome these harsh environments conditions the mangrove plants have a number of adaptations towards anoxia, high salinity and frequent tidal inundation. Since each species have their own adaptations mangrove tree species show distinct zonation pertaining to small environmental variations. The mangrove biome slows the flow of water and thereby enhancing sediment deposition in the area hence providing a ideal habitat for several marine species. In this investigation we measured the abiotic and biotic factors from two different red mangrove sites, using the continues belt transect technique. The abiotic factors that were measured in this experiment included temperature, dissolved oxygen, pH, conductivity, turbidity, nitrate levels, ammonia levels, phosphate levels, water depth, and light intensity. To increase the reliability of this investigation the data was collected by four separate teams, where each team surveyed both mangrove sites twice.

Table 1: Abiotic Factors Red Mangrove Site A (Green Turtle)

Table 2: Abiotic Factors Red Mangrove Site B (Green Turtle)

According to the abiotic factors collected both mangrove ecosystems have roughly the same air temperature, water temperature, dissolved oxygen, pH, conductivity, dissolved particles, and water depth. The abiotic factors for turbidity on the other hand vary greatly, where the turbidity value range from 25~40 in mangrove site A and 35~60 in mangrove site B, this variation could be a result of stirring up the sediment while collecting water samples, an example of systematic error within the investigation. In this investigation both mangrove sites were red mangroves therefore from the similarities observed in the following abiotic data we could provide supporting evidence to the theory of zonation for different mangrove species. From this we conclude that different species of mangrove thrive in areas containing preferable abiotic factors in which they have adapted to.

Above are displayed bar graphs of the organisms that were found in both red mangrove sites, where the red mangroves in site A were submerged in water and the red mangrove in site B were anchored in the soil. Since the mangroves has the ability to slows water flow through prop roots, it allows rich sediments to settle hence attracting organism in site A. Conversely the mangroves in site B is not submerged in the water therefore many of the organism are exposed, however there is a lack in variety of organisms. The prop roots of mangroves cover a large surface area to volume ratio and allow for the growing or plants species such as lichen or algae, and the abundance of these producers give rise to species of snails. From this we could observe the interaction between different organisms  and draw out appropriate food chain and webs to model the interaction between different organisms in the red mangrove ecosystem.

Ecology, Genetics, and Evolution...

The snail Cepaea nemoralis is a organism that could be found all across Europe, and scientist used their shells to study evolution and natural selection. The shell color of the snail is controlled by a single gene "C"with three alternative alleles, and in order of dominance the three alleles are brown, pink, and yellow. These different shell colors exhibits different thermal properties, and laboratory experiments have shown shells with darker colors, such as brown and pink absorb solar radiation more efficiently than light colored shells such as yellow. Due to the thermal properties of the shells, darker shells are better suited for colder climates as they can make the most of the small amount of heat around them, however they are not suited for warmer climates because they are more vulnerable to heat shocks since the take up heat readily. Snails with lighter hand on the other hand are better suited to warmer climates because they can tolerate prolonged sunshine and are therefore are better at with standing heat shocks. From a evolutionary perspective, the snails with the genes for a shell color suitable for their environment will be more likely to survive to reproduce therefore passing on their adaptive trait to the next generation. In other words due to natural selection there will be a larger distribution of darker colored snails at colder environments, conversely there will be a larger distribution of lighter colored snails at hotter environments. Visual selection also play a great role in the evolution of the Cepaea nemoralis snails, one of the many predators of the Cepaea nemoralis snail is the song thrush therefore the ability of the snail to camouflage with it's environment is detrimental in their survival. It was observed that yellow snails are heavily predated in the woodlands because they are more conspicuous against the dark background, where darker snails on the other hand had the advantage of camouflage to avoid predators, and survive to reproduce. So the possible variation between the colors of snails found in different environment could be a product of visual selection and micro-climatic selection, hence demonstrating the evolution of this species of snails through natural selection.

Cepaea nemoralis

AIDS stands for acquired immune deficiency syndrome, and people with AIDS are highly susceptible to opportunistic diseases, infections, and cancers that takes advantage of a collapsed immune system. The reason is because the virus that causes AIDS, is HIV (human immunodeficiency virus) and it mainly attacks the T cells in our immune system that are responsible for fighting pathogens. In HIV infection, evolutionary process occurs over the time span of a months to years, rapidly altering the makeup of the viral population from a single individual, this is because once inside the cell, it transcribes itself in reverse, using the enzyme reverse transcriptase to make DNA, the host cell then integrates this newly formed DNA into its own genome. Due to the sheer number and diverse variety of the HIV virus, many could not be eliminated. As an example of natural selection, the immune system targets the virus and eliminate the more susceptible ones leaving behind the viral mutants that has the ability to escape detection and elimination, these selected few then survive to reproduce giving rise to a stronger generation of virus, hence crippling the immune system and leaving the patient vulnerable of invading pathogens.

http://www.lanl.gov/quarterly/q_fall03/selection.shtml

HIV Virus

In every organism on this planet their physical characteristics and outward appearance are determined by genetics, where different combinations of alleles give rise to different traits that helps the organism survive in their giving environment, and as part of ecology different environment give rise to different species whom through the process of natural selection are able to adapt as a population hence evolution. So from this we could observe this relationship between evolution, ecology, and genetics.

Saving Marine Mammals

Earth’s ever changing climate have a great effect on marine life forms in the ocean, changing their natural habitats and driving them to the point of extinction. Of the 129 species of marine mammals an estimate of approximately one-quarter of them are current facing extinction. It is important to protect these animals in order to preserver the biodiversity as well as a functioning ecosystem because most of these mammals include top predators on the food chain, for example dolphins and polar bears. At Stanford University and the National Autonomous University of Mexico, researchers found out that by preserving 4% of the ocean this could play a crucial role in the protection of a vast majority of marine mammal species.

                  The researchers pinpointed areas of the ocean where conservation could protect the maximum number of species that are vulnerable to extinction, and overlaid maps where each marine mammal species is found, these composition of map revealed to them locations with the highest diversity of species. After pinpointing the 20 conservation sites that contains about 84% of all marine animals, the scientist also considered habitats of special importance to the mammal as well as locating breeding grounds and migration routes. It was found that these areas where all coincided with regions that are highly impact by human activity therefore this would make conservation difficult, but the ultimate goal is still protecting 4% of the worlds ocean in order to preserve some of the worlds most magnificent creatures.

Sea Otter: One of the endangered marine mammals

 Bibliography: http://www.sciencedaily.com/releases/2011/08/110829115431.htm:

Bio control Pesticides

Thailand is a tropical country located close to the equator, it is hot all year round and during the rainy season it is very humid. The recent flood not only devastated the lives and homes of countless Thai citizens, but also polluted the streets and rivers with un-sanitized water, this damp and humid environment makes it a perfect spawning ground for mosquitoes. Mosquitoes in Thailand are known for compromising people’s health and spreading several diseases such as malaria. The solution to this could be found in bio pesticides that contain a certain type of fungus that is pathogenic to mosquitoes; this makes it an effective means to reduce to number of mosquitoes and therefore reducing malaria transmission.

According to the study the effectiveness of the fungus on mosquitoes were conducted using both laboratory as well as field studies, where experimenters model estimates the “impact of different vector control intervention on the mosquito’s life cycle and the average number of mosquitoes that survive to transmit malaria.” The results from the studies and experiments show that the technique must be widely practiced as a community in order to successfully control malaria transmissions, whether the strategies involve fungal bio pesticides or insecticide treated bed nets (ITNs). This technique could be proven to be very help in the reduction of malaria transmittance rate, this technique when applied to the citizens of Thailand could prove to be beneficial in reduction the chance of adults and children to the exposure of diseases such as malaria.

Malaria carrying mosquito

Bibliography: http://www.sciencedaily.com/releases/2009/10/091001235445.htm

Genetically Engineering Natural Body Guards

The integration of ecology and molecular biology has resulted in many important advances in understanding the complex interactions between organisms and the underlying mechanisms. One of the many advances in combining the two sciences could be seen in the plant Arabidopsis thaliana L., an excellent model for investigating ecological interactions such as induced indirect defense. Induced indirect defense is a technique plants use to defend themselves against the feeding of herbivorous arthropods by releasing substances into the air called volatiles, which attracts natural enemies of the herbivores and the activities of these natural predators benefit the plant's fitness therefore making this technique evolutionarily advantageous for plants. For many plants species after the releasing of volatiles, a process known as herbivory, the compound called (E)-DMNT has been detected in the surrounding of these plants, and of the many species of plants Arabidopsis is one of them. Using Arabidopsis as a model for studying the compound (E)-DMNT, we could pinpoint certain enzymes that are responsible for the synthesis for the compound and apply it in genetic engineering in order to create pest resistance crops.

The first step in studying the ecological relevance of individual compound of the complex volatile is through understanding the chemical pathway that is genetically engineered to the transgenic plant. In the process of genetic engineering the sesquiterpene (3S)-(E)-nerolidol, a precursor for (E)-DMNT is required in order to create transgenic plants that releases the compound (E)-DMNT during herbivory. However earlier attempts to produce relevant amounts of sesquiterpene have failed due to the lack of farnesyl diphostphate (FPP), which is the precursor for (3S)-(E)-nerolidol, therefore targets with an abundance of FPP are required for the synthesis of sesquiterpene. More suitable target for sesquiterpene synthase to target include the cytosol and the plastids due to their abundance in FPPs, the mitochondria a site of ubiquitous biochemical biosynthesis on the other hand is much alike the cytosol and a the compartmentalization of the mitochondria allows it to regulate the production of (E)-DMNT making it the perfect target for sesquiterpene synthase. FaNES1 a strawberry nerolidol synthase, also a form of sesquiterpene synthase is targeted using CoxIV (cytochromes oxidase subunit IV) localizing it in the mitochondria, therefore making up the transgenic plant.

Chemical Pathway of (E)-DMNT with precursors of (3S)-(E)-nerolidol and farnesyl diphostphate (FPP)

In the experiment transgenic Arabidopsis and wild Arabidopsis are grown in containers, where in the transgenic plants CoxIV is fused with green fluorescent protein (GFP) to efficiently target the GFP to the mitochondria. Using a method called solid-phase micro extraction (SPME) the levels of volatile compounds are recorded from the plants during herbivory. The results collected show that the levels of (3S)-(E)-nerolidol detected from the transgenic samples are 20-30 times more than the compounds from wild plant samples, where for the transgenic samples 9 of 12 were recorded detecting the compound (3S)-(E)-nerolidol, and of the 9 transgenic samples 5 were detected with the compound (E)-DMNT during herbivory. The wild plants on the other hand were unable to cause the formation of either (3S)-(E)-nerolidol or (E)-DMNT during herbivory, unlike other plant species whom proved otherwise. The reason for this is because the rate in which (3S)-(E)-nerolidol is converted into (E)-DMNT is inversely proportional to the rate at which they are released during herbivory, however this could be regulated using jasmonic acid, which acts as a mediator.

(E) Undamaged Transgenic (F) Undamaged Wild Type, Jasmonic acid (G) Undamaged Transgenic, Jasmonic acid

Transgenic CoxIV-FaNES1 plants were successful in emitting both (3S)-(E)-nerolidol and (E)-DMNT compounds during herbivory, and from the study both compounds were successful in attracting predatory mites (P. persimilis) when the transgenic Arabidopsis were being eating by herbivorous arthropods such as spider mites (Tetranychus Urticae) and caterpillar (P. rapae). From these conclusions we utilize this defensive mechanism and applying them to improve pest resistance of crops, however there are also several problems concerning with the transgenic CoxIV-FaNES1 plants that were used in the experiment. The problem that was seen in the transgenic Arabidopsis plants was that both the first and second generation of the transgenic species suffered from growth retardation, this is due to the divergence of FPP to be synthesized to (3S)-(E)-nerolidol causing a uneven distribution leading to growth inhibition and greatly impacting the performance of the plant. So although the genetic modification of induced indirect defense could improve crop production and allow crop plants to generate control agents against arthropod pest infestation, at the same time also result harming the performance of the plant, therefore saying that even though genetic engineering could be beneficial there is also equal risks involved.

% of predators CoxIV-FaNES1 vs. Wild Type Plants

Work Cited:
1. Kappers, Iris. "Genetic Engineering of Terpenoid Metabolism Attracts Bodyguards to Arabidopsis." Science. 2005: n. page. Web. <http://stke.sciencemag.org/cgi/content/full/sci;309/5743/2070

2. M, Dicke. "ISOLATION AND IDENTIFICATION OF VOLATILE KAIROMONE THAT AFFECTS ACARINE PREDATOR-PREY INTERACTIONS - INVOLVEMENT OF HOST PLANT IN ITS PRODUCTION." JOURNAL OF CHEMICAL ECOLOGY. 02 1990: n. page. Web. <http://cel.webofknowledge.com/InboundService.do?SID=S1AGmejh7c5GN75K46d&product=CEL&UT=A1990CT40300008&SrcApp=Highwire&Init=Yes&action=retrieve&Func=Frame&customersID=Highwire&SrcAuth=Highwire&IsProductCode=Yes&mode=FullRecord>.

3. Kessler, Andre. "Silencing the Jasmonate Cascade: Induced Plant Defenses and Insect Populations." Science. 30 07 2004: n. page. Web. 7 May. 2012. <http://www.sciencemag.org/content/305/5684/665.abstract?ijkey=65037872d5afd6050cc21f838fe7bc11bd65feee&keytype2=tf_ipsecsha>.