Marmosets and their offspring: twins are better than triplets

01 Mar 2019 | Back to News, Publications and Annual Reports

Did you know that marmosets often have twins? And triplets? And sometimes even quadruplets?!

This species is known for its striking white ear tufts. These little primates weigh around 350 grams on average and live in stable extended families. (In this report, we describe how they live together.) Usually there is one monogamous breeding pair, which often has twins or triplets.

So many kids, that sounds nice and cosy!

It is with twins, but not if there are more than two. It is very difficult for the female to raise more than two offspring. She only has two nipples and she can’t produce enough milk to feed more than two. So this almost never turns out well, unfortunately, either in nature or here at BPRC: one of the marmoset babies often dies. Of course, we aim to prevent this happening in our breeding colony.

That is why we have researched whether we can predict if a mother will give birth to two offspring or more than two. Which factors play a role in this? In order to find out, our researchers took a close look at the birth data for the BPRC marmoset colony over the past nine years.

Did you discover anything special?

You bet! It turns out that mothers who were themselves born as twins have a stronger chance of giving birth to twins, and that mothers who were born as triplets have a stronger chance of giving birth to triplets themselves. We also discovered that the number of previous births and the mother’s weight at the time of conception play a role in the number of offspring per birth.

Good to know, but how does this knowledge help the marmosets?

It means that when we are breeding, we work as little as possible with mothers of triplets. The quality of marmosets’ lives in breeding colonies improves with healthy mothers who have a bigger chance of having twins instead of triplets. In other words: more twins and fewer triplets in our colony of common marmosets leads to an improvement in animal welfare!

To find out more, read this longer article.