The history of George Washington and slavery reveals Washington's changing attitudes towards slavery. The preeminent Founding Father of the United States and a slaveowner, Washington became increasingly uneasy with that ancient institution during the course of his life, and provided for the emancipation of his slaves after his death. Slavery in colonial America was ingrained in the economic and social fabric of several colonies including his native Virginia, and Washington inherited his first ten slaves at the age of eleven on the death of his father in 1743. In adulthood his personal slaveholding grew through inheritance, purchase and the natural increase of children born into slavery. In 1759, he gained control of dower slaves belonging to the Custis estate on his marriage to Martha Dandridge Custis. Washington's early attitudes to slavery reflected the prevailing Virginia planter views of the day and he initially demonstrated no moral qualms about the institution. He became skeptical about the economic efficacy of slavery before the American Revolutionary War when his transition from tobacco to grain crops in the 1760s left him with a costly surplus of enslaved workers. In 1774, Washington publicly denounced the slave trade on moral grounds in the Fairfax Resolves. After the war, he expressed support for the abolition of slavery by a gradual legislative process, a view he shared widely but always in private, and he remained dependent on enslaved labor. By the time of his death in 1799 there were 317 enslaved workers at his Mount Vernon estate, 124 owned by Washington and the remainder managed by him as his own property but belonging to other people. Washington had a strong work ethic and demanded the same from both hired workers and from the enslaved people who were forced to work at his command. He provided his enslaved population with basic food, clothing and accommodation comparable to general practice at the time, which was not always adequate, and with medical care. In return, he expected them to work diligently from sunrise to sunset over the six-day working week that was standard at the time. Some three-quarters of his enslaved workers labored in the fields, while the remainder worked at the main residence as domestic servants and artisans. They supplemented their diet by hunting, trapping, and growing vegetables in their free time, and bought extra rations, clothing and housewares with income from the sale of game and produce. They built their own community around marriage and family, though because Washington allocated the enslaved to farms according to the demands of the business generally without regard for their relationships, many husbands lived separately from their wives and children during the work week. Washington used both reward and punishment to manage his enslaved population, but was constantly disappointed when they failed to meet his exacting standards. A significant proportion of the enslaved population at Mount Vernon resisted the system by various means, including by theft to supplement food and clothing as well as income, by feigning illness, and by running away. As commander-in-chief of the Continental Army in 1775, he initially refused to accept African-Americans, free or enslaved, into the ranks, but bowed to the demands of war, and thereafter led a racially integrated army. Moral doubt about the institution first appeared in 1778 when Washington expressed distaste at selling some of his enslaved workers at a public venue or splitting their families. At war’s end, Washington demanded without success that the British respect the preliminary peace treaty which he said required the return of all enslaved people regardless of whether (or when) the British ostensibly freed them. His public statement on resigning his commission, addressing challenges facing the new confederation, made no explicit mention of slavery. Politically, Washington felt that the divisive issue of American slavery threatened national cohesion but was largely controlled by each state, and he never spoke publicly about it. Privately, Washington considered plans in the mid 1790s to free his enslaved population. Those plans failed because of his inability to raise the finances necessary, the refusal of his family to approve emancipation of the dower slaves, and his own aversion to separating enslaved families. Instead, his will provided for emancipating all of his enslaved people, the only slave-owning Founding Father to do so. Because many of his enslaved people were married to the dower slaves, whom he could not legally free, Washington’s will stipulated that, except for his valet William Lee who was freed immediately, his enslaved workers be emancipated on the death of his wife Martha. She freed them in 1801, a year before her own death and a year after her husband's, but she had no option to free the dower slaves, who were inherited by her grandchildren.

Tetsuya Shimizu (清水 哲也, Shimizu Tetsuya, born April 5, 1983) is a Japanese professional wrestler, currently signed to New Japan Pro-Wrestling (NJPW) as the masked Bushi (stylized in all capital letters). In NJPW, he is a one-time IWGP Junior Heavyweight Champion, a one-time IWGP Junior Heavyweight Tag Team Champion and a current record-tying four-time NEVER Openweight 6-Man Tag Team Champion. Through NJPW's working relationship with the Mexican Consejo Mundial de Lucha Libre (CMLL) promotion, Bushi has held the CMLL World Welterweight Championship. Prior to adopting his current persona Shimizu worked under the ring names T28, Tetsuya, and Tetsuya Bushi in All Japan Pro Wrestling (AJPW). While in AJPW, together with Super Crazy, Bushi won the 2010 Junior Tag League and won the U-30 Tag Team Tournament in 2008 with Kushida. Bushi spent 2009 working in Mexico for International Wrestling Revolution Group (IWRG), gaining international experience before returning to AJPW in 2010. Having worked for AJPW for most of his career, Bushi transferred to NJPW in April 2012.

Bird migration is the regular seasonal movement, often north and south along a flyway, between breeding and wintering grounds. Many species of bird migrate. Migration carries high costs in predation and mortality, including from hunting by humans, and is driven primarily by availability of food. It occurs mainly in the northern hemisphere, where birds are funneled on to specific routes by natural barriers such as the Mediterranean Sea or the Caribbean Sea. Migration of species such as storks, turtle doves, and swallows was recorded as many as 3,000 years ago by Ancient Greek authors, including Homer and Aristotle, and in the Book of Job. More recently, Johannes Leche began recording dates of arrivals of spring migrants in Finland in 1749, and modern scientific studies have used techniques including bird ringing and satellite tracking to trace migrants. Threats to migratory birds have grown with habitat destruction especially of stopover and wintering sites, as well as structures such as power lines and wind farms. The Arctic tern holds the long-distance migration record for birds, travelling between Arctic breeding grounds and the Antarctic each year. Some species of tubenoses (Procellariiformes) such as albatrosses circle the earth, flying over the southern oceans, while others such as Manx shearwaters migrate 14,000 km (8,700 mi) between their northern breeding grounds and the southern ocean. Shorter migrations are common, including altitudinal migrations on mountains such as the Andes and Himalayas. The timing of migration seems to be controlled primarily by changes in day length. Migrating birds navigate using celestial cues from the sun and stars, the earth's magnetic field, and mental maps.

Tetsuya Shimizu (清水 哲也, Shimizu Tetsuya, born April 5, 1983) is a Japanese professional wrestler, currently signed to New Japan Pro-Wrestling (NJPW) as the masked Bushi (stylized in all capital letters). In NJPW, he is a one-time IWGP Junior Heavyweight Champion, a one-time IWGP Junior Heavyweight Tag Team Champion and a current record-tying four-time NEVER Openweight 6-Man Tag Team Champion. Through NJPW's working relationship with the Mexican Consejo Mundial de Lucha Libre (CMLL) promotion, Bushi has held the CMLL World Welterweight Championship.

Bird migration is the regular seasonal movement, often north and south along a flyway, between breeding and wintering grounds. Many species of bird migrate. Migration carries high costs in predation and mortality, including from hunting by humans, and is driven primarily by availability of food. It occurs mainly in the northern hemisphere, where birds are funneled on to specific routes by natural barriers such as the Mediterranean Sea or the Caribbean Sea.