No, in the days before the flood, people lived much longer. Methuselah lived the longest of any person.
The explanation which always satisfied me is the following. Adam and Eve were created to live forever, in perfect conditions. But when they sinned, death entered the world, although not immediately. Adam finally died when he was 930 years old, in Genesis 5. Many of the ancients before the flood lived for centuries, read Genesis 5 to see the people and their ages. Longevity was the rule, not the exception!
So in chapter 6 of Genesis, God becomes angry with human beings for various reasons. He picked Noah, a righteous man to build the ark. It was not just a flood from the sky, but also the "waters of the deep" Gen. 7:11, opened up. So this was a BIG flood. Plus, if there had been a protective canopy over the earth, as some postulate, by dumping that canopy on the earth, all people, plants and animals were open to the excessive radiation from the sun, and the mutations caused by it. I think other things also entered the environments of people, as the first mention of alcohol is after the flood. Perhaps the yeast needed to make alcohol came from the rain or the juvenile water??
So you have totally new conditions in the earth. A these conditions accelerated, people began to suffer more and more under a genetic load - that is mutations which favoured diseases and resulted in shorter living times. This continued up to the time of Abraham, who died at the "ripe old age" of 175 years (Genesis 25:7), Isaac who lived 180 years (Gen. 35:28), Jacob who lived 147 years (Gen. 47:28), his son Joseph at 110. (Gen. 50:26)
There is a real downward trend from Adam and Methuselah to the end of Genesis, after the flood in length of life. Moses is recorded to have died at age 120 in Deut. 34:7. So things level off. Yet as we know today, the person who lives to 120 is the exception to the rule, not the rule.
I also believe God's prohibition to the Jews against marrying sisters and cousins, which begins in Lev. 18:6-18, is because of the genetic load which narrowed the genome considerably, especially considering Abraham married his half sister, and his sons also married relatives from Haran. In fact, this prohibition continues today, because of the possibility of interbreeding producing bad mutations. I once worked teaching handicapped students, and there was a family whose parents were cousins. Four out of the five children had facial deformities and were mentally handicapped, as a recessive trait was expressed in the children.
So the perfection created in Eden, allowed those early inhabitants of the earth to live much longer than we live today, and Methuselah lived the longest of them all.
Dearly beloved friend, with all due respect to you, the Holy Bible of GOD's Word did not mention and have anything to do with any of this that you have proclaimed and in the method of science. In the Kingdom of this world and it's wisdom, men and science predictions are limited to only what their mind is able to perceive, apart from GOD's power and wisdom, who art in Heaven and have been the creator of all, the provider of all and the decider of all, in all kind things.
For they wandered off on their own ways, unable to be fruitful and faithful to their creator, away from GOD and were scattered all over the earth, each one ignorantly moved on to his or her own traditions and doctrines and languages of men. They remained unfruitful in thinking and in recognizing the creator and started creating and devising their own things and did what was pleasing to their sight. This very similar act was recorded in Genesis, GOD's true story witnessing the builders of the tower of babel and only to those who belong to HIM, whom HE will and found, HE Helped them see, even us through CHRIST and the HOLY SPIRIT.
And those whom GOD made Himself known, now able to know and see things differently in opposite direction and distinctive among carnal men and women, whose confession is based on theory and predictions and some of them were never true nor came true but wound in a circle time after time. But compared to the Kingdom of GOD of truth. HIS by the Help of the HOLY SPIRIT and directed by CHRIST and in our blessed Spiritual discernment, grandly in limitation highlights to us more towards, GOD, who is the creator of all, HIS will and HIS plans and HIS actions for and towards all mankind and all creation, who mankind were initially created and made in HIS image, gave them HIS power and authority, to bring to subdue over all other creations and multiply and dwell all over the earth, bringing justice and peace in the physical visible world, which solely belongs to I AM that I AM. And HE remain as the actual SPIRITUAL invisible original always in existence owner, forever and ever the creator from the beginning and ever ruler over all HIS creation, even in Heaven and on earth, spiritual and physical, Amen.
Let our spiritual attention turn away from carnal science and perceive Kingdom sound doctrine knowledge justifications from the beginning of Genesis in the Holy Bible;
After Adam and Eve's selfish feelings and desires of the flesh/carnal, which gave in to the crouching sin, and from then on their generation after generations were enslaved themselves to the same master(sin and death) and satan till today remain either the approved or disapproved by GOD's will, initiator/tester to faithfulness. Only sin and death became the ruler of this earth then on, taking opportunity of GOD's righteousness and the weaknesses of mankind. Death was the wages for all who sow in sin, at the end of the day, as which was first proclaimed by GOD, cautioning Adam first and then Adam to Eve.
In the Kingdom of GOD's rules and conditions, sin is the justification of one's disobedience against it's Ruler and death is their wages. Death first destroys the spiritual side of mankind, away from HIS image and then the physical side, away from eternal health and life. So the lifespan of flesh and blood is shortened. These were for the generation of Shem, after Noah, whom GOD continued with until they became an Israelite nation and govern by GOD'S Law. There were prolonging of health and life span because of the washing ceremonies and sacrifices to keep them from harms way.
Yet for the non-Jews, they were govern by the Law written in their conscience. Everything happened naturally by what they have and believed and yet GOD still ruled over all of them, allowing them in their ignorance for time being until now. And also HE allowed anyone who wanted to come into the Jewish faith.
Yet in all of this, only GOD is the final decision maker, for and over all creation in Heaven and on earth, including all mankind with HIM or against HIM or without HIM. HE reigns on High as the only Ruler to fear and tremble, who is HEAD over all power and all authority and all rulers and all forces whom HE created and placed, spiritual and physical, in the Heavens and on earth, who are representing and acting at HIS command, as HIS chosen spiritual and physical government, governing on behalf of HIM. Serving on HIS behalf to bring HIS justice everywhere, even though they may seem as injustice, to a carnal eye, Even using those representatives who have turned their backs and are against HIM and HIS Goods, who are all in all, still approved as HIS visible or invisible instruments used now and then for HIS purpose, decides once and for all, every single creation's health and life span, even their existence or non-existence, great or less great and etc.
HIS Holiness and righteousness, towards the physical realm, HE overall able to decide whether to lengthen or shorten, give or to take health and life or even provide salvation and pay for them later, in order to fully justify to all, physical and spiritual, at the end, HE is and have been I AM that I AM, through Moses and through fully in CHRIST JESUS, the Alpha and Omega over Heaven and earth, the Potter of merely clay, the author and finisher of our faith, always perfect, right and fair, have no favorites and etc.
One simple Scripture written in the book of Proverbs, justify that science is not the distinguisher and decider of mankind's ways and their span of lives but only GOD All-Mighty.
"Men make plans but only GOD decides."
In Hinduism, it has been a common practice marrying their cousins. Are all of their children effected in defects? From them came many bollywood handsome actors and many world pageants winning actresses.
As it is written in 1 Corinthians 3;18-21, that;
"Let no one deceive himself. If anyone among you thinks that he is wise in this age, let him become a fool that he may become wise. For the wisdom of this world is folly with GOD. For it is written, HE catches the wise in their craftiness, and again, 'The LORD knows the thoughts of the wise, that they are futile.' So let no one(believer) boast in men."
