I think Malthus had it wrong. It isn't population that causes war and pestulance. It is war and pestulance that cause people to have as many kids as they can in the hope that some will survive.
The last half century has seen a little noticed blood bath of civil war and often related famine and drought to Africa, and a handful of other countries. With just a handful of exceptions, every nation with a fertility rate of 6 children per woman per lifetime or more in the world (and most with 5 children per woman per lifetime or more) has experience civil wars and other mass death horrors in recent history. A comprehensive list of those nations below the fold spells out this relationship.
Which countries still have high fertility rates?
The highest is Niger with 8 children per woman (currently fighting a civil war with the Taureg liberation front, most recent coup in 1999).
In the 7 and up range are: Yemen (civil war has continued on and off since at least 1994 to the present), Somalia (no functioning government), Angola (civil war persisted from 1975-2002 and still persists in oil rich regions), Uganda (about 300,000 people were killed in a 1971 genocide, civil war persisted from then until 1985, another civil war has been pending from at least 1997 to the present) and Mali (famine killed 100,000 in 1973-1974 and droughts hit in the 1980s, the most recent coup was in 1991, the most recent civil war ended in 1994).
In the 6 and up range are Afghanistan (civil war from 1979-2001 which scattered resistence continuing), Burkina Faso (most recent coup in 1987), Burundi (160,000 killed in civil war 1972-1973, 150,000 dead in ethnic conflict 1993-1996, most recent coup 1996 with attempts in 2001, clashes with rebels are contiuing), Liberia (civil war 1989-2003), Ethiopia (droughts killed hundreds of thousands in the 1970s and a million in 1984, civil wars from 1974-1988 and 1991-2001, food shortages and ethnic clashes persist), Democratic Republic of Congo (3.3 million have died in civil war from 1996-2002, leader assassinated 2001, most recent coup attempt 2004), Chad (civil war continously since 1966), Republic of Congo (civil war 1997-2003), Malawi (one party state from 1964-2004), and Sierra Leone (civil war killed 10,000 from 1991-1996, thousands more were killed when civil war resumed from 1998-2001).
In the 5 and up range are Benin (single party rule 1960-1989), Bhutan (absolute monarchy isolated from the world almost completely until the 1990s), Dijibourti (civil war 1991-1994), Eritrea (civil war and then war to maintain independence from 1962-2001, also famines while part of Ethiopia), Guinea (reign of terror by government in 1970s, coup in 1984, attempted army mutiny in 1996, refugee crisis from neighboring liberia and Sierra Leone from 2001-present), Madagascar (coup in 1972 followed by dictatorial rule through 1993, cholera and cyclones cause mass death in 2000, ever election since 1993 has been disputed), Maldives (dictatorship since 1978; population is only 340,000), Mauritania (civil war 1977-1979, coup in 1984, slavery continues to exist here), Mozambique (civil war 1974-1992, famiunes in the 1980s as a result, floods displace 1 million people in 2000), Nigeria (civil war 1967-1970, military rule interrupted by coups predominanted from 1970-1999, hundreds if not thousands have died since 2000 in religious clashes between muslims and animist/Christian groups), Oman (small monarchy with intrafamily coup in 1970), Pakistan (bloody split from India in 1947, civil war/war with India 1970-1972, coup in 1977, suspicious death of President in 1988, coup in 2001, guerilla violence is longstanding in Kashmir and in certain other parts of the country), Rwanda (large scale massacre of Tutsis in 1963, coups in 1973 and 1990, civil war through 1993, 1 million Tutsis massacred in 1994) Senegal (low level civil war since 1982), Tanzania (one party rule from 1964-1992), Togo (dictatorial rule since 1967), and Zambia (droughts in 1980s and 1990s, food riots in 1990 and 2002, 17% of the population has AIDs).
Screw free market economics and even full fledged multiparty democracy. China and Cuba, to cite just a couple of nations, have developed quite briskly and brought fertility rates under control without it. Many nations in Africa simply need a basic absence of armed conflict accompanied by economies that function at least well enough to prevent mass starvation more than anything else and won't achieve any development until this baseline is achieved.
The worst thing European colonialists did was not so much what happened while they ran much of Africa, but their abrupt departure in the 1960s and the artificial boundaries that they left behind, which created a power vacuum before legitimate function civilian governments could be established sufficiently to continue on their own. The half century of fumbling around with guns and politics to try to establish legitimate governments afterwards has killed millions of people and made all of Africa suffer.