Population and the increased use of fossil fuels needed to support people when they step out of poverty, are the two greatest environmental challenges of the 21st Century.
Currently we share this planet with another 7 billion people, and it’s growing each second.
In 1800, the world population peaked at 1 billion, since this time the growth has expedited.
In 1950, the average woman in Bangladesh, had seven babies and a woman’s life expectancy was just 50 years old. However, in 2015 Bangladesh women, have less babies only 2.5 babies on average and the life expectancy is now 70 years. 
The idea of two child families in China, India,Vietnam shows the idea of smaller families is feasible across a host of religions, and culturally held pre-conceived ideas are no longer held.  The population Council’s research uncovered “the mean ideal family size has become closely clustered around 2.2 in most countries.” This decrease in family sizes is unprecedented in human history. 
The second issue, relates to the increased use of fossil fuels. This is directly attributed to increased income distribution. With education comes the knowledge to escape poverty, most countries are making steady progress- the gap between the richest and poor is smaller, although one billion still remain in poverty. However getting out of poverty is just the beginning, people who worked hard will continue along the path, seeking a ‘good life’. This leads to an increase in the consumption of fossil fuels such as Coal, Oils and Natural Gas, thus increasing the carbon dioxide emissions into the environment.
 Bangladesh’s population has grown from 50 million to 150 million people,15 million live in the capital Dhakah,
 Melinda and Bill Gates family planning. http://www.gatesfoundation.org/What-We-Do/Global-Development/Family-Planning
How to Attain Population Sustainability- http://www.overpopulation.org/pop-sustainability.html
 Through education – girls are against marrying young – women in the past feared being left with no children, now vaccines save the life of millions of children – the biggest obstacle -child mortality is now gone.
 Many have gone for $1 per day to $10 per day – and have enlisted help of electrical appliances and transportation using fossil fuels.