Question 1
Yes, the genus Phoxinus exists. The common species of the genus is the minnow (Phoxinus phoxinus). Minnow is a small freshwater fish with dark spots forming an attractive banded effect. The fish has a small mouth, small scales, and large eyes. During spawning seasons, male fish develop bright red colors which are spectacular to attract the female. Minnows feed on plant debris, molluscs, algae, insects and crustaceans (Farrell 567). The existence of this species in a river indicates the availability of oxygen content in the riverbeds and streams. The feeding behavior of the fish involves shoaling and schooling. The action benefits the fish by allowing foraging and predator avoidance. The shoaling behavior exhibited by the fish allows for the success of feeding (Farrell 572). This concept ensures small predator activities per individual or species enabling them to scan for food and enhance quicker detection. For instance, a larger shoal identifies food faster. However, in the case of predation, the fish would tend to reduce its feeding rates.
The two species described by the scientist involve character displacement since when they co-exist; they tend to feed on separate parts of the river. Their foraging techniques change to reduce the rate of completion experienced in the habitat. For example, the species described here feed on separate parts of the river with one feeding at the top and the other feeding at the bottom part of the riverbed.
The species when placed in the same habitat when obtained from the wild show that the P gothica is a highly competitive species depending on the absence of predators and other very competitive species. This behavior shows the high rates of feeding superiority and concurs with Darwin’s theory of natural selection where the species with stronger character traits survives. Thus, P. dethmetalensis remains as having the dominant feature hence remain as the dominant species in the habitat.
Question 2
The environmental framework begins with observations that give an insight of space and time about nature. The observation is a concept that the researcher has identified and needed a solution. The views may be incorrect based on the biasness of that observer. The next step is the proposal of explanations depending on the views. The explanations are theories of the models to account for the observations made in the previous stage. The explanations and theories give rise to the hypothesis that is the stem for the particular ecological research. The researcher then creates a null hypothesis that is subject to change based on the experimental outcome. The next step is the experiment part. This procedure involves the determination of whether the process previously described by the hypothesis is correct based on the experimental results. The final step involves making an analysis that either support or refute the hypothesis. It requires that the data collected is strategically analyzed.
Question 3
Starting date: 13th October Population= 23 individuals
End date: 3rd June Rate of growth= 0.04/day
Increased Rat population= (0.04 X 232)/ (23)= 9 rats
Rat Population= 23+9= 32 rats
A roof rat (also called the Alexandrine rat) originates from South East Asia and is common in attics (Best 258). Roof rats have large ears and pointed noses. These rats eat meat and grain with their common nesting areas being above the ground (Best 259). Their peak activities begin from dusk till dawn, for example, they are nocturnal. The exponential growth rate gets determined by the availability of food and suitability of the habitat.
Question 4
The computed data involve the following species in the habitat:
Dipodomus merriami 33
Ammospermophilus harrisi 29
Neotoma albigula 12
Chaetodipus penicillatus 21
Thomomys bottae 2
Spermophilus variegatus 1
Tamias dorsalis 1
Spermophilus tereticaudus 1
Species richness (S) = 8
Computing Shannon Weiner diversity index:
Shannon-Weiner diversity index= Absolute value of (-1.5233) = 1.5233
Evenness (E)= H/Hmax
Hmax = Ln(8) = 2.08
E = 0.7324
Based on the findings of the Shannon diversity index and evenness of the distribution, it shows that the population of species is sparsely distributed in the habitat. This data shows a sign of scarcity of food resources. Dipodomus merriami represents the kangaroo rat that thrives more in the deserts while Spermophilus tereticaudus is the round-tailed ground squirrel. The potential geographic area of the habitat is the arid and semi-arid areas. The creatures are not suitable for mark-recapture method due to scattered distribution of these species in the habitat with some sample as low as one count in the first capture. The method is always restricted to a single species when used.
Question 5
Moorish idols marked = 100
Moorish idols second captured= 100
Marked =16
Unmarked= 84
Let;
the number first marked = X = 100
the number second catch= Y = 100
Total population = N
Therefore: X/N = M/Y; 100/N = 16/100
Total population = 625
Moorish idol is a real organism with its scientific name being Zanclus cornutus. The fish lives in shallow waters and majorly exist from about three to one hundred and eighty meters deep in the sea. The conditions of water in this fish are murky, and at times they stay in the clear water. The method would not have considered the migration analysis of the fish based on how it changes its habitat.
Question 6
The article describes the possible extinction of species due to climate change. The paper describes reasonable predictions of species based on the implementation techniques based on the international strategies employed to prevent the environmental degradation. The article describes a meta-analysis concept with 131 published predictions that explain the species that are bound to become extinct based on values of the Markov chain Monte Carlo analysis (Urban 571). This process involves the use of random effects of based on random effects of the meta-analysis. The study takes into consideration the sample size.
The concept takes into account the extinction risks including taxonomic groups, increased temperatures, dispersal assumptions and other deviance information criterion. The paper describes that credible interval of sample analysis applies. From the analysis method, the author describes that there is a strong correlation between the current environmental degradation and future rates of extinctions that are present. Therefore, the method defined a pre-established range that would determine the rate of extinction. This field is called the minimum extinction threshold and takes into account the interaction between species, evolution and dispersal differences (Urban 575).
Work Cited
Best, L. W. "Food of the roof-rat, Rattus rattus rattus (L), in two forest areas of New Zealand." New Zealand Journal of Science 12 (1969): 258-267.
Farrell, Anthony P. Encyclopedia of fish physiology: from genome to environment. Academic Press, 2011.
Urban, Mark C. "Accelerating extinction risk from climate change." Science 348.6234 (2015): 571-573.
