Moa

Any of 11 species of large flightless birds (ratites) native to New Zealand. All the moas are now extinct, but before being exterminated by the Maori this group included the largest birds to exist in historic times, including Dinornis giganteus, which stood taller than 2 meters at the shoulders when fully grown, much higher when it extended its long neck.

New Zealand lacks any large native mammals, and the moas grew to great sizes to fill the ecological niches usually taken by mammalian species such as buffalo, deer, cattle, etc. Some grazed the open grasslands in the manner of cattle but most lived in forest and browsed the trees and vegetation there. The only native predator capable of attacking a moa (and even then, only a small one) was the large Haast's eagle, also now extinct.

When the Polynesian Maori colonized New Zealand a millennium or so ago, they found the large, landbound birds no match for their spears, and soon hunted them to extinction. The colonists' canine and rodent companions would have found the moas' large eggs quite delicious as well, which probably accelerated the big birds' decline, as they reproduced quite slowly.

By the time the first Europeans encountered New Zealand several centuries afterward, the Maori had long exhausted their supply of easy meat. The moas were no more.

The extinction of the moas at the hands of the Maori is strong evidence against the myth of the so-called "noble savage." It's humanity that's at odds with nature, not merely Western civilization.

There is a New Zealand moa that's not yet extinct, however. The MOA project (Microlensing Observations in Astrophysics) carries out observations of a wide variety of astrophysical phenomena, using gravitational lensing to achieve great precision. Their homepage is at http://www.vuw.ac.nz/scps/moa/

MOA is a measurement for the accuracy of a gun, and stands for "minutes of arc" (or minute of accuracy or minute of angle; there is some confusion on this point). In any case, minute does not refer to time, but to degrees; an accuracy of one minute of arc means that the weapon does not deviate from the target by more than 1/60 of a degree; at 100 yards, that is equivalent to a deviation of an inch.

While MOA seems to provide a nice, clean cut evaluation of the accuracy of a weapon, it is in many ways a highly subjective measurement, and affected by (at least) the following factors:

• The weapon: Obviously the weapon itself has a vast effect on the MOA. A sniper rifle would be considered useless if it didn't have an MOA of at least 1/2, most rifles are between 1 and 5, and many pistols and muzzle loaders have an MOA of around 5, though there are certainly exceptions; some muzzle loaders and pistols have been found to have an sub-1 MOA, while a US Army issue M16 can (in theory, at least) have an MOA up to 4 before it is considered unsuitable for use.
• The distance: MOA is, nominally, a measurement independent of the distance, but obviously that doesn't really make sense. As a stupidly extreme example, a 1 MOA gun cannot hit Sol from Earth, even if its MOA might suggest it could easily make that shot. A more practical example is that while a .22 pistol might be quite accurate at 50 yards, the small weight and relatively light charge will mean that by the time it reaches 1000 yards, gravity and air movement will have changed its final resting place quite dramatically. For this reason, MOA is sometimes specified with a distance, such as "1 MOA at 200 yards".
• The ammunition: It is generally agreed that expertly done handloads provide better MOA than factory produced ammunition, probably due to better consistency. In addition, a 'hotter' round with more powder behind it will tend to have a better MOA; there is effectively no difference between the ammunition in an M16 (.223) and in a backwoods varmit huntin' .22, except that the M-16 has a whole lot more powder (and thus, velocity).
• The shooter: I would argue that this is the most important factor in the overall MOA. A skilled shooter can compensate for wind, distance, and movement much better than an untrained and unskilled user, and thus can produce far more accurate results at longer distances.

Note that I have no real idea what I'm talking about (this is primarly based on book lernin and my relatively limited experience with firearms), so any corrections or additions would be welcome.

Mo"a (?), n. [Native name.] Zool.

Any one of several very large extinct species of wingless birds belonging to Dinornis, and other related genera, of the suborder Dinornithes, found in New Zealand. They are allied to the apteryx and the ostrich. They were probably exterminated by the natives before New Zealand was discovered by Europeans. Some species were much larger than the ostrich.

© Webster 1913.