The presence of pain in an animal cannot be known for certain, but it can be inferred through physical and behavioral reactions. Specialists currently believe that all vertebrates can feel pain, and that certain invertebrates, like the octopus, might too. As for other animals, plants, or other entities, their ability to feel physical pain is at present a question beyond scientific reach, since no mechanism is known by which they could have such a feeling. In particular, there are no known nociceptors in groups such as plants, fungi, and most insects, except for instance in fruit flies.
Who do specialists believe can feel pain?
vertebrates

There are a variety of watersports in Cork, including rowing and sailing. There are five rowing clubs training on the river Lee, including Shandon BC, UCC RC, Pres RC, Lee RC, and Cork BC. Naomhóga Chorcaí is a rowing club whose members row traditional naomhóga on the Lee in occasional competitions. The "Ocean to City" race has been held annually since 2005, and attracts teams and boats from local and visiting clubs who row the 24 kilometres (15 mi) from Crosshaven into Cork city centre. The decision to move the National Rowing Center to Inniscarra has boosted numbers involved in the sport.[citation needed] Cork's maritime sailing heritage is maintained through its sailing clubs. The Royal Cork Yacht Club located in Crosshaven (outside the city) is the world's oldest yacht club, and "Cork Week" is a notable sailing event.
How many rowing clubs are in Cork?
five

The waterwheel appeared in Chinese records during the Han. As mentioned by Huan Tan in about 20 AD, they were used to turn gears that lifted iron trip hammers, and were used in pounding, threshing and polishing grain. However, there is no sufficient evidence for the watermill in China until about the 5th century. The Nanyang Commandery Administrator Du Shi (d. 38 AD) created a waterwheel-powered reciprocator that worked the bellows for the smelting of iron. Waterwheels were also used to power chain pumps that lifted water to raised irrigation ditches. The chain pump was first mentioned in China by the philosopher Wang Chong in his 1st-century-AD Balanced Discourse.
What commandery was the creator of the waterwheel-powered reciprocator from?
Nanyang