Scientists have managed to increase monkey brain size by splicing them with human genes in what seems like an eerie plot to an all-too-familiar horror Sci Fi film.

Seriously, what could go wrong here?

The "Planet of the Apes" type of experiment was done by Japanese and German researchers.

They took a gene, ARHGAP11B, known to direct stem cells in human brains. Then they injected it into the dark matter of marmoset fetuses.

The Surprising Findings

What they discovered was shockingly intriguing: the monkey brains grew in size and became more human-like. This is precisely what the gene does in humans as well.

In particular, the brains got more advanced neocortexes. These are the parts that control cognition and language.

Now you know why people are drawing parallels between this research and the popular "Planet of Apes" movie. In the film, the primates could talk and come up with complex attack plans against their human oppressors.

The findings were published in the scientific journal, Science.

At about day 100 of the experiment, the brains of these fetuses were almost as large as they usually are:

We found indeed that the neocortex of the common marmoset brain was enlarged and the brain surface folded.

This was according to Michael Heide. Heide was the study author.

Scientists discovered that the neocortex is the latest section of the brain to evolve. On some level, this proves that ARHGAP11B may be responsible for the growth in human brain sizes during human evolution.

But to avoid any horrors that might have come with rearing monkeys with bigger and human-like brain sizes, the scientists couldn't let them live. They were aborted over what the researchers termed as "unforeseeable consequences."

This was probably for the best.

The study was carried out by Planck Institute of Molecular Cell Biology and Genetics, a German research outfit. The institute worked in conjunction with Central Institute for Experimental Animals, a Japanese research organization.

In many ways, this study is a big reminder of the 2011 movie, "Rise of the Planet of the Apes." In the movie, genetically modified primates rise up and turn against humans to take over the world.