User:Meg Dillon8/sandbox

Article Evaluation

Overall, the article was satisfactory. It was slightly short in length, but the quality of the article was reasonable. The article was coherent, with a neutral and factual tone. The information was relevant however some of the information could have been put into another article. For example, in the first few paragraphs there were definitions for biomonitor and 2 definitions for biological indicator. This was a large volume of information that could have been split up. I would recommend defining the subject of the article first (bioindicator), explaining it and then defining the other terms later in the article. In addition to this, having two definitions for the same term could have been confusing for some readers.

In terms of the grammatical content and organisational aspect, the article was very well done. Despite the article being relatively short, 34 sources were used. There were citations in almost every paragraph and the links worked. The works cited were legitimate, correctly cited and were peer reviewed scientific journals. The article was also well organised into separate and distinct paragraphs. As the reader, I found it clear and easy to understand when each of the different types of bioindicators were discussed separately (plants, microbes, macroinvertebrates). The use of several examples enhanced the article, however more examples could be added to increase comprehension.

Lastly, the talk page demonstrates some minor confusion with the layout and flow of the article. One user seems to be confused with the difference between the definitions presented at the start of the article. Another person has attempted to organise the article and has suggested some changes that can be made. The article is part of the WikiProject Environment, a project which aims to enhance and ameliorate the coverage of environmental issues on Wikipedia.

This is the link to the article that I reviewed: Bioindicator

Bibliography (Week 5)

-Species is bioindicator of water quality. However there are conflicting reports as to the strength and effectiveness

-What is a bioindicator and how well does the species fulfill this role?

-Examined the suitability by looking at the general tolerance to pollution and the roles played by the organic environment and eutrophication

Article Outline (Week 6) Purr

- In the first paragraph explain what felids and genets are

- Add more detail to the mechanism section

- Get rid of the list in the next section and try to reconfigure the information into a more coherent and tied together paragraph

-Add some more detail and see if you can find other reasons for the purring(expand on what is already there)

'''Week 7 (Add to article)-Copy and Pasted Article into Sandbox. New contributions are BOLDED and certain other things were added/deleted. Check original Purr article for reference.'''

Purr
A purr is a tonal fluttering sound made by some felid and genet species. '''Felids are a family of mammals that belong to the order Carnivora and are informally known as cats. This designation includes larger, outdoor cats and the domestic cat (Felis catus). Genets are a member of the genus Genetta and are slim, animals with features similar to cats. Their features include retractile claws and the ringed tail.'''

Although true purring is exclusive to certain animals, other animals produce purr-like vocalization. Animals that produce purr-like sounds include mongoose, bears, badgers, foxes, hyaenas, rabbits, squirrels, guinea pigs, tapirs, ring-tailed lemurs, and gorillas while eating. '''Animals purr for a variety of reasons including to express happiness, or fear and as a defense mechanism. It has also been shown that cats purr to manage pain and soothe themselves. Purring is a soft buzzing sound, similar to a rolled 'r' with a fundamental frequency of around 25 Hz. This sound occurs with noticeable vibrations on the surface of the body, varies in a rhythmic pattern during breathing and occurs continuously during inhalation and exhalation. The intensity and length of the purr can also vary depending on the level of arousal of the animal.'''

Mechanism
The mechanism by which cats purr is an object of speculation, '''with different theories proposed. An early theory was that purring is a hemodynamic process where sound is produced as the blood runs through the thorax.'''

Although the mechanism has not yet been fully elucidated, recent studies have inferred it could be the result of oscillatory mechanisms in the central nervous system. Studies have also shown that purring can be caused through electrically stimulating the infundibular region of the cat's brain, suggesting central control.

Vocal folds/laryngeal muscles
'''It appears that purring likely originates from the intrinsic laryngeal muscles. These muscles facilitate the opening and closing of the glottis, which is the space between the vocal chords. When the vocal chords are separated, the purr sound is produced.'''

Purpose
'''In domestic cats, many signals that occur when interacting with humans, seem to originate from when the animal was dependent on the mother. Cats have been observed to purr for most of their lifespan, starting from when they were young and suckling from their mother'''. Purring may have developed as an evolutionary advantage as a signalling mechanism of reassurance between mother cats and nursing kittens. Post-nursing cats often purr as a sign of contentment: when being petted, becoming relaxed, or eating. Some purring may be a signal to another animal that the purring cat does not pose a threat.

In addition to this, cats have been shown to have different sounding purrs depending on the situation. Purring sometimes seems to be a way for cats to signal their caretakers for food. This purring has a high-frequency component not present in other purrs. '''These are called solicitation purrs (when the cat is looking for something) and non solicitation purrs and are distinguishable to humans. In a study, 50 humans were subjected to playbacks of purrs recorded in solicitation and non solicitation situations at the same amplitude. Humans regularly judged the solicitation purrs as less pleasant and more urgent as the non solicitation purrs.''' This variety of purring seems to be found more frequently in cats in a one-to-one relationship with a caretaker. '''Similarities have previously been drawn between an infant crying and the isolation cry of domestic cats. The high frequency aspect of the purr can subtly exploit humans sensitivity to these cries, which makes it more difficult to become habituated and ignore this. Using sensory biases in communication between species provides the signalers (cats) with a productive way to increase the standard of care received.'''

'''One hypothesis for purring is that there are healing powers associated with the behavior. It has been proposed that the vibrations from purring can cause healing in cats and humans. Vibrations in the frequency range of 20-150 Hz have been thought to promote bone growth because bones may harden due to the pressure. Cats purring in the range of 25-50 Hz has therapeutic proprieties for bone and 100 Hz for skin and soft tissues according to researchers. It is also possible that purring is a low energy mechanism to stimulate bones and muscles since cats have adaptations which allow them to conserve energy for long periods of time. Since cats have been domesticated far more recently, compared to other domestic species such as dogs, they display a lower number of bone and muscle abnormalities. Due to this, it has been suggested that cats purring could help relieve muscle and bone related degeneration such as+ dysplasia, osteoporosis and osteopnia that have a higher incidence in canids.'''

'''Cats often purr when distressed or in pain, such as during labor. In cats, there are three stages of labor. In the first stage, the uterus begins to contract, the cervix relaxes and the water breaks. During this stage, the cat begins to purr which is hypothesized to be a self relaxation technique.''' This purring may trigger a cat's brain to release a hormone which helps it in relaxing and acts as a painkiller.