yhernaiz's blog

Insects migrate in wind highways Perfect Paragraph

Researchers have found that migrating insect use highways in the to sky help them speed up their trips. Insects like butterfly and moths have used these highways to find better winds that could take them in a particular direction for many kilometers. They are capable of traveling for approximately100km per hour. One of the questions that scientist asks is: How do they find these winds? It seems like they use internal compasses to find the winds. Researchers have found that insect in the Mediterranean use this complicated methods to beat wintering waterholes and northerly climes during summer. The most interesting part is that only few of the insects end up in the wrong way.

They still don’t know how this mechanism works, but for know they are using special radar that can detect insects movement up to a kilometer in the air. Knowing how insects use this mechanism could be helpful to predict models in the future for invasive pest in the country, like moths.

Comparing C. eurytheme and C.philodice Growth Rate in Different Temperatures- Introduction Perfect Paragraph

Insects use a variety of strategies to increase the fitness and survival of the species. Bet hedging, when an organism produces many progeny to increase their individual chances of survival, and Diapause, a quiescent period where development is suspended during adverse conditions (Roff, 1993), are two examples of these strategies. Colias philodice and Colias eurytheme are two sympatric, closely related species that utilize these strategies to survive. These species also occupy the same habitat and utilize the same food source and host plants. When two species depend on the same resources, one species will drive the other to extinction, yet these Pierid butterflies coexist. This study investigated the methods these species employ to coexist.

C. philodice and C. eurytheme can be distinguished by their wing color: C. philodice is yellow with blank band at the tips of the wings and C. eurytheme is light orange with black bands at the tip of the wings (Wang & Porter, 2004; Porter& Levin, 2007). It was hypothesized that these two species can interbreed randomly, allowing them to coexist. However, a study done by Taylor (1972) demonstrated that these species are sexually isolated under most natural conditions, which refutes this hypothesis. Another group studied host plant evolution in hybrid species and showed a clear difference in maturation strategies between C. eurytheme and C. philodice. Even though they grow at the same daily rate (DGR) C. philodice pupate a day earlier (with a lower body weight) than C.eurytheme. This life-history difference may provide a seasonally fluctuating fitness trade-off that could help explain the coexistence of these butterflies. (Porter & Levin, 2007). We propose that C. philodice completes an extra generation before entering diapause placing it one generation ahead of C. eurytheme, and thus giving the species an advantage. Since the extra generation will develop in cooler temperatures, we hypothesize that C.philodice will do better in colder temperatures than C. eurytheme.

Comparing C. eurytheme and C.philodice Growth Rate in Different Temperatures- Introduction Perfect Paragraph

Insects use a variety of strategies to increase the fitness and survival of the species. Bet hedging, when an organism produces many progeny to increase their individual chances of survival, and Diapause, a quiescent period where development is suspended during adverse conditions (Roff, 1993), are two examples of these strategies. Colias philodice and Colias eurytheme are two sympatric, closely related species that utilize these strategies to survive. These species also occupy the same habitat and utilize the same food source and host plants. When two species depend on the same resources, one species will drive the other to extinction, yet these Pierid butterflies coexist. This study investigated the methods these species employ to coexist.

C. philodice and C. eurytheme can be distinguished by their wing color: C. philodice is yellow with blank band at the tips of the wings and C. eurytheme is light orange with black bands at the tip of the wings (Wang & Porter, 2004; Porter& Levin, 2007). It was hypothesized that these two species can interbreed randomly, allowing them to coexist. However, a study done by Taylor (1972) demonstrated that these species are sexually isolated under most natural conditions, which refutes this hypothesis. Another group studied host plant evolution in hybrid species and showed a clear difference in maturation strategies between C. eurytheme and C. philodice. Even though they grow at the same daily rate (DGR) C. philodice pupate a day earlier (with a lower body weight) than C.eurytheme. This life-history difference may provide a seasonally fluctuating fitness trade-off that could help explain the coexistence of these butterflies. (Porter & Levin, 2007). We propose that C. philodice completes an extra generation before entering diapause placing it one generation ahead of C. eurytheme, and thus giving the species an advantage. Since the extra generation will develop in cooler temperatures, we hypothesize that C.philodice will do better in colder temperatures than C. eurytheme.

Comparing C. eurytheme and C.philodice Growth Rate in Different Temperatures- Introduction Perfect Paragraph

Insects use a variety of strategies to increase the fitness and survival of the species. Bet hedging, when an organism produces many progeny to increase their individual chances of survival, and Diapause, a quiescent period where development is suspended during adverse conditions (Roff, 1993), are two examples of these strategies. Colias philodice and Colias eurytheme are two sympatric, closely related species that utilize these strategies to survive. These species also occupy the same habitat and utilize the same food source and host plants. When two species depend on the same resources, one species will drive the other to extinction, yet these Pierid butterflies coexist. This study investigated the methods these species employ to coexist.

C. philodice and C. eurytheme can be distinguished by their wing color: C. philodice is yellow with blank band at the tips of the wings and C. eurytheme is light orange with black bands at the tip of the wings (Wang & Porter, 2004; Porter& Levin, 2007). It was hypothesized that these two species can interbreed randomly, allowing them to coexist. However, a study done by Taylor (1972) demonstrated that these species are sexually isolated under most natural conditions, which refutes this hypothesis. Another group studied host plant evolution in hybrid species and showed a clear difference in maturation strategies between C. eurytheme and C. philodice. Even though they grow at the same daily rate (DGR) C. philodice pupate a day earlier (with a lower body weight) than C.eurytheme. This life-history difference may provide a seasonally fluctuating fitness trade-off that could help explain the coexistence of these butterflies. (Porter & Levin, 2007). We propose that C. philodice completes an extra generation before entering diapause placing it one generation ahead of C. eurytheme, and thus giving the species an advantage. Since the extra generation will develop in cooler temperatures, we hypothesize that C.philodice will do better in colder temperatures than C. eurytheme.

Comparing Colias eurytheme and C.philodice Growth Rate in Different Temperatures

Abstract:
Colias philodice and Colias eurytheme are two sympatric, closely related species that utilize various strategies to survive in the same habitat. These species also utilize the same food source and host plants. When two species depend on the same resources, one species can drive the other to extinction, yet these Pierid butterflies coexist. This study investigated the methods these species employ to coexist. We propose that C. philodice completes an extra generation before entering diapause, thus giving the species an advantage. Since the extra generation will develop in cooler temperatures, we hypothesize that C.philodice will do better in colder temperatures than C. eurytheme. We grew these two species at two different temperatures and measured the pupal weight, the duration of the larval stage, and the effective daily growth. Our results show that although C. philodice did better in colder temperatures than C. eurytheme, the difference was not significant enough to account for C. philodice ability to coexist with C. eurytheme.

Introduction:
Bet hedging and diapause are two strategies used by insect to increase the species fitness. Bet hedging is when an organism produces a great amount of offspring to make sure that some will survive different conditions. Diapause is a period where development is suspended (Roff, 1993). Colias philodice and Colias eurytheme are sympatric and closed related species, these species occupied the same habitat and utilizes the same foodplant. They can be distinguished by their wing color: C. philodice is yellow with blank band at the tips of the wings and C. eurytheme is light orange with black bands at the tip of the wings (Wang & Porter, 2004; Porter& Levin, 2007). In nature when two species depend on the same resources one species can drive the other to extinction, but with these to pierid butterflies coexist. They thought that one of the reason the still coexist is because they interbreed random but in a study done by Taylor (1972) demonstrate that these species are sexually isolated under most natural conditions. A study of host evolution in hybridzation species they found a clear difference in maturation strategies from C. eurytheme and C. philodice. Even though they grow at the same daily rate (DGR) C. philodice pupate one day earlier (with a lower body weight) than C.eurytheme. This difference was cause by females pupate later than males. This life-history difference may provide a seasonally fluctuating fitness trade-off that could help explain the coexistence of these butterflies. (Porter & Levin, 2007). Our hypothesis is that before entering diapause one of the species, C. philodice, is one generation ahead than C. eurytheme, giving them an advantage. C.philodice will do better in could temperature than C. eurytheme.

Methods:
Five females of C. eurytheme and six of C. philodice were collected from fields in Sunderland, South Deerfield, MA and New Haven, CT. The females were placed in plastic containers containing cuttings of the host plant Trifolium pratense, with the cuttings kept fresh with wet tissue paper wrapped around the stem. Butterflies were fed daily with honey solution (Porter & Levin, 2007). For each female we transferred neonate larvae to six Petri dishes, with ten larvae per dish. Each dish contained cuttings from white clover (Trifolium repens) kept with moist tissue paper wrapped around the stem. The dishes were distributed between two growth chambers at 21°C and 16°C with a 24 hour long-day photoperiod until pupation (Porter & Levin, 2007). The dishes cuttings were changed when needed and the dishes were rotated within the chamber to reduce any effect of microenvironmental variation. Dishes were checked every day for new pupae. Each pupa was weighted and placed in a cup until eclosion to identify gender.

Results:
Our hypothesis is C.philodice will grow better in colder temperature than C. eurytheme. We found that temperature has a significant effect on pupal weight and DGR. Duration does not have strong effect on DGR as the pupal weight did.

Conclusion:
Our results show that although C. philodice did better in cold temperature than C. eurytheme, the difference was not significant enough to account for C. philodice ability to coexist with C. eurytheme.

Future Work:
In our experimental design was that we kept the chamber temperature constant, instead we will fluctuate the temperature during the day.

Acknowledgement:
Special thanks to Emma Rudie, Seth Rowley, Adam Porter and NEAGEP Staff. This research was supported by the National Science Foundation Grant (NSF HRD 0450339): Dr. Charlena Seymour, Dr. Sandra Petersen, Dr. Julian Tyson, Dr. Donald Fisher, and Dr. Donald St. Mary.

Literature Cited:
Bradford MJ & Roff DA. 1993. Bet Hedging and the Diapause Strategies of the Cricket Allonemobius fasciatus. Ecology 74(4):1129-1135.
 
Porter AH & Levin EJ. 2007. Parallel evolution in sympatric, hybridizing species: performance of Colias butterflies on their introduced host plants. Entomologia Experimentalis et Applicata 124: 77-99.

Taylor OR. 1972. Random vs. Non-Random Mating in the Sulfur Butterflies, Colias eurytheme and Colias philodice (Lepidoptera: Pieridae). Evolution 26(3):344-356.

Wang B & Porter AH. 2004. An AFLP-Based Interspecific Linkage Map of Sympatric, Hybridizing Colias Butterflies. Genetics 168:215-22.

Butterflies Evolved UV-vision to Help Find Mates Perfect Paragraph

Butterflies have a wide variety of patterns and wings colors. This diversity may have led the evolution of vision in these insects. One of the reasons that butterflies have to evolve their vision is because of wing-color mimicry. Many butterflies use mimicry as a defense mechanism to avoid predators. A side effect of this mimicry is that it is harder for species that look alike to identify their own species when they have to find a mate.

Researchers have found that Heliconius butterflies are born with a duplicate gene that allows them to see ultraviolet colors, but they also have UV-yellow pigment on their wings. There is a possibility that this UV pigmentation help them survive by facilitating the search of mate, giving them more time for reproducing and eating. They believe that by changing to a new way of making yellow is easier for mimicry butterflies to identify each other. Of 14,000 butterflies around the world, only Heliconius butterflies from Mexico and South America are known to have the duplicate gene.

Mate odur choice in mouse

This semester I'm taking a hybrid zone seminar and this week reading was about variation in mate preference across a house mouse hybrid zone. These groups of researchers were trying to study the influence of hybridization on patterns of preference for parental type odorant mate signals across a unimodal hybrid zone between the two European subspecies of the house mouse, Mus musculus musculus and M. m. domesticus. They used field and laboratory mice to observe the reaction of the mouse towards the urine. The mice collected from the field were obtained from 46 different locations across the hybrid zone. They collected urine from trains derived from wild-caught mice sample from areas where the two species are in contact. To test their behavior the place the urine at the two ends of a Y shape maze. They place one mouse at a time and measured the time of sniff and ratio of preference. During duration of sniff they found no variation between females and males across the hybrid zones. For ratio of preference Musculus males preferred musculus females odours whereas domesticus males preferred domesticus females odours, and the preference was stronger on the musculus side.

Insects migrate in wind highways

Researchers have found that migrating insect use highways in the to sky help them speed their trips. Insects like butterfly and moths have used this highways to find better winds that could take them in a particular direction for many kilometers. They are capable of traveling for 100km per hour. How do they found these winds? It seems like they use internal compasses to find the winds. Researchers have found that insect use this complicated methods to beat wintering waterholes in the Mediterranean and northerly climes during summer. The most interesting part is that few of the insects end up in the wrong way.

They still don’t know how this mechanism work, but for know they are using special radar that can detect insect movements up to a kilometer in the air. Knowing how insects used this mechanism could be helpful to predict models in the future for invasive pest in the country like moths.

Source: http://news.bbc.co.uk/2/hi/science/nature/8500619.stm

New Orleans after Hurricane Katrina Perfect Paragraph

During this past week I was participating at a conference at New Orleans, Louisiana. As part of my conference they gave us a tour around the most affected area after Hurricane Katrina.

New Orleans city have levees to prevent flood in storms and hurricanes because the city is below sea level. But when Katrina hit New Orleans in 2005 the pressure of the water was so strong that broke 5 levees leaving the city under water. In some parts of the city the levels of water were greater than others. One of these areas was the Lower 9th Ward, this area was extremely affected by the water. You can still see part of the damage cause by the hurricane. Many people lost their houses and never came back because they couldn't afford to rebuild their homes, other had the blessing of having flood insurance or receiving help from the different celebrities like Brad Pitt.

New Orleans is still recovering from this horrible nightmare; they are a lot of renovation going around the city. Not only the houses suffer from this tragedy but also the Universities around suffered. Universities like Dillard University, Southern University of New Orleans and University of New Orleans lost a lot during the flood. Dillard University was the worst hit, all the campus was flooded but they still continue to give classes at the Hilton Hotel until they could go back to the campus.

For now only 80% of the people are back, but it has been really hard for them to get back to their feet. But not all was bad from this tragedy, now they are rebuilding environmental friendly houses and some universities have better classrooms and labs for their students. During summer and spring break they are a lot of people that come from around the states to help people in need. Also programs involve in rebuilding houses for families that lost them during the hurricane.

New Orleans after Hurricane Katrina

During this past week I was participating at a conference at New Orleans, Louisiana. As part of my conference we had tour over the most affect area after Hurricane Katrina. New Orleans city is below sea level and for that reason they have levees to prevent flood in storms and hurricanes, but when Katrina in 2005 pass by New Orleans the pressure of water broke 5 levees leaving the city under water. In some part of the city the level of water were greater than others. One of this areas was the lower 9th floor, this areas was very affected by the water after Katrina and you can still see part of the damage cause by the hurricane. Many people lost their houses and never came back because they couldn't afford to rebuild their housing, other had the blessing of having flood insurance or receiving help from the different celebrities like Brad Pitt that rebuild some houses. New Orleans is still recovering from this horrible nightmare, they are a lot of renovation going around the city. Not only the houses suffer from this tragedy but also the Universities suffered around. Universities like Dillard University, Southern University of New Orleans and University of New Orleans lost a lot during the flood. Dillard University was the worst hit, all the campus was flooded but they still continue to give classes at the Hilton Hotel until they could go back to the campus. For now only 80% of the people are back, but it has been really hard for them to get back to their feet. But not all was bad now they are rebuilding environmental friendly houses and some university have better classrooms and labs for their students. They are still a lot of people that come from different states and programs to help rebuild many of the houses and buildings.

Attached they are some pictures of the new and old houses.

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