We studied the effects of urbanization on periphyton density and species richness in the local Amethyst Brook. Amethyst Brook is a good site for a study due to it being conservation land where houses butt right up against some points of the river. This allowed us to chose one site that represented close proximity to urbanization and two other sites farther away from human development. We constructed a three-slide apparatus to place at each of the three sites, removing them at one and two week intervals. Microscope analysis of the slides provided us with multiple species types and overall density. We hypothesized that urbanization would have an effect on periphyton in the brook, and predicted that there would be lower densities and less species at the site closest to houses. We also hypothesized that our week two collection would comprise of higher densities of periphyton. Our data showed no correlation between periphyton density and proximity to urbanization. Interestingly, there was also a decrease in density across sites 1 and 3 after two weeks. This was due to heavy rains during the beginning of the second week that increased turbidity and strength of the water flow. A more elaborate experiment with multiple sites and longer ‘grow periods’ would be necessary as a follow up to this pilot study.
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Comparative anatomists have discovered numerous intermediates between this most primitive type of eye and the vertebrate eye, such as: eye cups; pinhole eyes; camera-type eyes with a single lens; reflecting mirror eyes; and compound eyes with numerous ommatidia, all of which lends support to Darwin’s theory.
A monophyletic origin for the eye is supported by the observation that all metazoans share the same visual pigment, rhodopsin
The observation that Pax 6 homologs of both mammals and insects are essential for eye morphogenesis led to the idea that Pax 6 might be the universal master control gene for eye morphogenesis and evolution
The protein-coding regions of Pax 6 are highly conserved in evolution, as are some of the regulatory sequences in the promoters and enhancers.
There have been many different approaches taken to regrow degraded areas of the Amazon rainforest. Humans have acted as seed dispersal agents with some success (Gagetti, 1998) but seeds are a food source for many animals and constant seeding of an area is necessary to overcome predation. Research has also been conducted on the importance of avian foragers for seed dispersal of fleshy fruits, which showed that birds are the main seed dispersing agents in many forests around the world (Puckey, 1996). In light of this previous knowledge, our study looks to understand the role of fruit color preference in selected Amazonian parrot species. The information gleaned from this study will be used as a stepping stone in directing the selection of fruit-producing plants that will attract parrots to areas of degraded forest. We hope to support the use of frugivorous birds as a potential seed vector in rainforest restoration.
The three species of parrots we plan to study are the blue-fronted Amazon (Amazona aestiva), red-browed Amazon (Amazona rhodocorytha) and Kawall’s Amazon (Amazona kawalli). All of these parrot species have experienced a decline in numbers over the last 25 years (Figueira, 2015) as a result of deforestation. The parrots species we plan to study prefer old-growth forests, the destruction of which has negatively impacted food availability and increased predation due to lack of canopy cover. All three of these species will take and eat fruit, but the types of fruit preferred by each have not been studied yet. Our research would shed light on the diets of these particular parrots, which could aid in conservation efforts.
Swaths of the Amazon rainforest have fallen victim to slash-and-burn agriculture where felled forest land is used to grow subsistence crops. When these farm plots are abandoned, the land will eventually return to forest but the regrowth process can take 200 years (Wilson, 1988). The agricultural practices of cutting, burning, and weeding largely eliminate mechanisms of on site regeneration making it more difficult to regrow woody pioneer species (Pedlowski, 1997). Seed dispersal has been suggested as a mechanism of facilitating forest regeneration. However, the dependence on seed dispersal slows succession because many of the animal species that routinely disperse seeds, such as avian frugivores, do not frequent large forest openings. This tendency to forage away from large openings is due to both a lack of food sources, and a lack of cover from potential predators (Wilson, 1988). In order to attract seed-dispersing birds, we propose to identify and plant indigenous fruit bearing plant species to facilitate visitations to clearings caused by slash-and-burn agriculture.
Food color preference of avian foragers has not been widely studied. Globally, the most common fruit color of bird-dispersed plants are red and black. Other preferential fruit colors include blue and purple, while orange and green are rarely chosen (Janson 1983). Fruit colors are commonly considered to increase the conspicuousness of ripe fruit in order to attract birds to disperse the enclosed seeds. The preference of fruit color in avian foragers may be due to a variety of factors. The factors hypothesized to affect food color choice include background color, the prevalence of one color, and nutritional value associated with certain colors (Willson, 1990). In our study, we would examine food color preferences of three parrot species living in areas of the Amazon rainforest that are in need of ecological restoration.
Vitamin B6, also known as pyridozine, naturally occurs in many foods we eat such as poultry, fish, starchy vegetables, and non-citrus fruits. People may also choose to take a dietary supplement containing viatmin B6 in order to satisfy daily nutitional needs. Vitamin B6 is required for more than 100 enzyme driven reactions involved in metabolism. Healthy levels of vitamin B6 contribute largely to the production of modd influencing hormones such as serotonin and norepinephrine. Vitamin B6 also assists with the conversion of carbohydrates in food into glucose for storage and ATP. Most importantly, however, this key vitamin helps control levels of the amino acid homocysteine in the blood. This amino acid is largely associated with heart disease, although more reasearch is needed to determine exactly how the two are interrelated.
Food color preference of avian foragers has not been widely studied. In North America, the most common fruit color of bird-dispersed plants are red and black. Other preferential fruit colors include blue and purple, while orange and green are rarely chosen (Janson 1983). Fruit colors are commonly considered to increase the conspicuousness of ripe fruit in order to attract birds to disperse the enclosed seeds. The preference of fruit color in avian foragers may be due to a variety of factors including background color, the prevalence of one color, and nutritional value associated with certain colors. In our study, we would examine food color preferences of bird species in areas of the Amazon rainforest that are in need of ecological restoration. Frugivorous birds may play an important role in the restoration process due to their efficiency in seed dispersal (Gagetti, B L, et al, 1996). We hope to direct the selection of plants that produce certain fruit colors to aid in the restoration of degraded forests
These fall monarchs look exactly like all other monarchs. However, they are physiologically different, and emerge from the pupa in a state called reproductive diapause. Diapause is basically a period of suspended development; these individuals do not have the mature internal sex organs (Monarch Butterfly Fund). This allows them to stay alive until the next spring, when they’ll be able to fly north and lay eggs. This migration is the key part to success of the monarchs’ annual life cycle. At the end of the winter, monarchs end diapause, becoming ready to mate and lay eggs as they move northward. Once they become reproductively active, they’ll only live another few weeks. Their eggs then mark the start of another annual life cycle, as the first generation of monarchs is born again.
A lichen consists of two or more partners that live together symbiotically, with both of them benefitting from the alliance. One partner is a fungus termed as the mycobiont. While the other is either an algae, photobiont (usually green) or a cyanobacterium, sometimes called blue-green algae although it is more closely related to bacteria than algae. The algae or cyanobacterium is able to use sunlight to produce essential nutrients by photosynthesis that feeds both organisms. The fungus creates a foundation, known as a thallus, in which they both live. The fungus also produces chemical compounds that may act as sunscreen to protect its photosynthetic partner.