The world population will be officially recognized as reaching the seven billion mark sometime on Oct. 31 by the United Nations Population Fund.

That's a big leap in less than a century, considering that world population in 1927 was just two billion.

With seven billion people on Earth in 2011, many are asking the question: How many is too many?

The seven billion milestone with projections of more growth, said Babatunde Ostimehin, executive director of the United Nations Population Fund, is a challenge, an opportunity and a call to action.

Global population will reach seven billion on Oct. 31, with another billion people projected on Earth by the year 2025. The world's population is projected to reach 10 billion by the end of this century.

World Population by the Billions

1 billion - 1804
2 billion - 1927
3 billion - 1959
4 billion - 1974
5 billion - 1987
6 billion - 1999
7 billion - 2011

The challenges, of course, are a major concern for most. Among them are these:

--Food shortages, and lack of economic opportunity.

--Damage to the global environment.

--Energy and water shortages.

--Aging and healthcare solutions.

--Access to education, information, and technology.

The arrival of the seven billionth person is cause for profound global concern, said Jeffrey D. Sachs, director of The Earth Institute at Columbia University, in a piece written for CNN. It carries a challenge: What will it take to maintain a planet in which each person has a chance for a full, productive and prosperous life, and in which the planet's resources are sustained for future generations?

How, in short, can we enjoy 'sustainable development' on a very crowded planet?

As the the population reaches seven billion on Earth in 2011 and growing, that's the general concern among many experts. Each additional person on Earth requires food, water, and energy and each additional person on Earth contributes to waste. Each additional person needs resources like education and technology to best contribute and flourish, but each additional person is also a drain to resources in some respects at least.

And the needs will be the greatest in poorer nations and regions which are growing at the fastest rates, since there is a clear correlation between poverty and larger families throughout the world. The result is potentially of widening of the gap between the have's and the have not's of the world.

Among the solutions for global needs amid seven billion population on Earth include the following:

--A rapid transition away from fossil fuels.

--More global technology infrastructure including fiber-optics which connect the world.

--Smallholder farm development in poor countries and regions to empower the people to produce for themselves, and better distribution of food.

Hunger and poverty are challenges we all face together -- we must act now, said Pierre Ferrari, president of Heifer International, according to MSNBC.

Our global agricultural system can feed 7 billion people today. It is a matter of equity and distribution.

Heifer International, a non-profit focused on helping the poor become self-sufficient, provides cows, goats, and other livestock to people in some 50 other countries for food.

The real issue to be faced is the next 30 years when another two billion people will be with us, Ferrari said. It is forecasted that the global food supply will need to double to meet the needs of the global population. The small holder farmer (650 million of them) produces 70 percent of the world food today.

In the end, the assessments are consistent that people will need education, food, water, and technology so that they can best help themselves in a crowded world slim in resources among the people and regions that need it most. The challenge, of course, will be in making that happen while protecting the environment at the same time.