▲According to the Book of Exodus, God inflicted plagues on Egypt to persuade the Pharaoh to free the Israelite slaves. The Pharaoh only accepted God's request after the tenth plague. Proponents of biblical archaeology have offered up two theories to explain the events.

▲One scientific explanation is that a rise in temperature led to an extreme drought and turned the Nile red. The heat generated a proliferation of pyrophytic algae, which caused the color to change.

▲Another hypothesis is that the river changed color because of earthquakes triggered by a volcanic eruption. The quakes disturbed dissolved iron deposits in the water, which mixed with gases released by the tremors to form ferrous hydroxide (rust), turning the water red.

▲According to Exodus, Pharaoh Ramesses II still resisted freeing the Israelites from slavery. Accordingly, another divine punishment was imposed: the invasion of the river bank and beyond by thousands of amphibians.

▲According to the British physicist Colin Humphreys, this "curse" was a direct consequence of the first. With diminishing levels of oxygen in the water, the frogs fled the river and migrated to land. Meanwhile, numerous fish died in the Nile.

▲The Egyptians prayed for an end to this terrible series of plagues. But a third punishment was bestowed upon them.

▲Another modern explanation suggests the proliferation of parasites was a direct result of the increasingly unhygienic nature of the Nile as its waters became more polluted.

▲A swarm of flies followed the lice infestation. While the Egyptians suffered greatly from this latest plague, the Israelites were not at all affected by this airborne assault.

▲In his book, Colin Humphreys believes the insect invasion was entirely due to the demise of the amphibians, whose main food source were these flying insects—less frogs, more flies!

▲Another theory suggests that the lack of clean water and so many dead animals simply attracted more flies to the region.

▲The Bible says that Ramesses II lied to Moses and told him that he would free the slaves. When his deception was discovered, Egypt was punished with the demise of its domestic animal population.

▲One explanation for the death of so many animals is the so-called cascade effect. Infestations of flies and lice promoted by the lack of clean water, plus the decimation of the frogs (natural predators of the insects), were all factors in causing this latest "plague."

▲Humphreys theorizes that stable flies transmitted fatal viruses to horses and cows.

▲The volcanic eruption theory underlines the belief that escaped carbon dioxide resulted in festering boils and infected wounds.

▲One simple theory suggests that the tempest was a rare hail storm that included thunder and lightning. Although scarce, it is possible for such weather phenomena to occur in desert regions.

▲Nadine von Blohm of the Institute of Atmospheric Physics of Germany theorizes that the event was a rain of stones caused by a volcanic eruption.

▲Exodus says that God delivered this punishment in order to destroy crops in the region. Again, the Israelites escaped the curse.

▲According to Humphreys' book 'The Miracles of the Exodus,' locusts invaded Egypt on the back of a change in climate, and that the crop destruction was because of the force of the hailstones and/or volcanic activity.

▲A second theory is that the cold weather and damp soil created an ideal breeding ground for the flying pests.

▲One theory is that a dense sandstorm may have been responsible for the phenomenon. Such storms occur in the deserts of Egypt today.

▲The volcanic theory posits that the ashes caused by the eruption eclipsed the sun and left Egypt in darkness.

▲Modern scholars believe that deaths of firstborn children had its origin in a cultural habit at the time. Firstborn children had the privilege of being fed first. They ate food contaminated by locust feces and died of disease.

▲

Another theory is that the firstborns died due to carbon dioxide released by the volcano. The vulnerable infants would have died from inhalation of the toxic gas.

▲A seventh plague brought with it a frightening storm of hail, ashes, and fire, which fell from the sky.

▲British physicist Colin Humphreys, author of the book 'Miracles of the Exodus' (2003), argues that an extreme drought was responsible for changing the water of the Nile, which precipitated the series of events. Others theorize that a volcanic eruption caused the sequence of plagues 3,500 years ago. Canadian biologist Siro Trevisanato, who wrote the book 'The Plagues of Egypt' (2005), is a proponent of this idea.

▲The volcanic eruption theory posits that the toxic gases released by the earthquakes starved the water of oxygen, forcing the frogs to flee to dry land.

▲According to Colin Humphreys, the drought led to the multiplication of lice eggs. The parasite was a common scourge in ancient Egypt, and the reason why many people shaved their heads.

▲According to biologist Werner Kloas of the Leibniz Institute in Germany, boils appeared due to the multiplication of insects, which stung and bit the hapless Egyptians.

▲

The first divine plague occurred when Pharaoh Ramesses II refused to free the Israelites. The water of the Nile, which symbolized fertility, turned to blood.

▲According to the Bible, the first infant of both humans and animals died. Only the Israelites, who had been warned to mark their doors with the blood of a lamb, would be saved. Pharaoh Ramesses II lost his son in this plague.

▲

Exodus states that total darkness descended for three days.

▲

Exodus has it that the Egyptians were next afflicted with boils on the skin.

▲

The Plagues of Egypt were a series of calamities that, according to the biblical Book of Exodus, God inflicted on Egypt to convince the Pharaoh to release the Israelites from slavery. Although the majority of historians believe the events to be allegorical, there are scientific theories which suggest the "plagues" are in fact an unfortunate sequence of natural disasters.

Browse the gallery and explore the theories surrounding the Plagues of Egypt.