SEVENS IN NATURE
This is a chapter from the book, Biblical Mathematics, written by Evangelist, Ed F. Vallowe, quoted on http://www.angelfire.com/az/rainbowbridge/seven.html.

Life operates in a cycle of SEVENS. Changes take place in the body every SEVEN years. There are SEVEN bones in the neck, SEVEN bones in the face, SEVEN bones in the ankle, and SEVEN holes in the head. Most births are multiple of SEVENS. The hen sits three weeks (21 days); the pigeon two weeks (14 days); after having laid eggs for two weeks. Of 129 species of Mammalia (sic) the majority have a period from conception to birth of an exact number of weeks, a multiple of SEVEN.
Human physiology is constructed on a law of SEVENS. Children are born to mothers in a certain number of weeks usually 280 days, a multiple of SEVENS. Fevers and intermittent attacks of gout, ague, and similar complaints have a period of operation of SEVEN, FOURTEEN or TWENTY-ONE days known as critical days.
All departments of nature are marked all over with mathematics. In this realm practically everything is in SEVENS. Notice next time the shape of frost when it crystallizes on the window. Notice the small snow flakes. It is wonderful how God formed everything in a pattern of SEVENS.
It would be well for the reader to always remember the SEVEN means COMPLETENESS or SPIRITUAL PERFECTION. Whenever you come to a SEVEN in the Word of God read the meaning and the message is plain.
SEVEN is found 735 times in the Bible.  Ex. In the Book of Revelation the number SEVEN is used throughout. There are SEVEN churches, SEVEN Spirits, SEVEN stars, SEVEN seals, SEVEN trumpets, SEVEN vials, SEVEN personages, SEVEN dooms, and SEVEN new things. [This is very fitting, for the Book of Revelation is all about what happens at the COMPLETION of this world. God created all things in the beginning and then took six days of restoring His creation and then rested on the SEVENTH day. (Genesis 2:1-3). He appointed SEVEN days for the week, and most, if not all advanced nations reckon time in that way: SEVEN days to the week. Few ever stop to think of why there are SEVEN days in a week. Do atheists and infidels give God and the Bible credit for it?
There are SEVEN notes in the musical scale. All other pitches are only variations of these. When the musician uses the eighth note he goes back to “do” and starts over. Man named the notes but God fixed the sounds, even as God fixed the days of the week, and man named them.