Rare twin turtles sharing one egg found in batch of 105 eggs in Malaysia

Not unheard of, though.

Oct. 6, 2021

Rare twin turtles sharing one egg found in batch of 105 eggs in Malaysia

Despite the sheer magnificence of nature, the world around us also brings with it brutal reminders of the fragility of life.

Such was the case when turtle conservationists from the Malaysia-based Juara Turtle Project (JTP) discovered something peculiar on the sands of Tioman Island.

Extremely rare, but not unheard of.

In a photo posted on Instagram and Facebook, JTP shared a particularly unique discovery while excavating turtle nests – twin green turtle (Chelonia mydas) hatchlings that shared the same egg.

Yes, it is possible for two turtles to share the same egg. IMAGE: @juaraturtleproject / Instagram

But of course, I did just mention the brutality of nature. So you'd be wrong to assume that the photo above shows two living turtle hatchlings, unfortunately.

"These twin hatchlings are a little small compared to the other hatchlings in the clutch," JTP said on their Instagram post.

"This is likely because these twin hatchlings shared the same egg yolk sac, meaning they also shared the same space and nutrient supply. Thus, there was likely not enough space and nutrients for both hatchlings to grow properly."

Despite the twins not surviving, JTP expressed amazement at how much they grew into late-stage development inside the egg, despite the physical constraints and the lack of nutrition to nurture both turtles' growth equally.

Since the turtles became part of a group of stragglers (turtles that are still alive but didn't make it to the sea, or dead embryos), JTP plans to preserve them for educational purposes.

While twins are a natural occurrence in wildlife, the probability of it actually happening is extremely low.

Especially among sea turtles, it's quite a rare phenomenon.

"Twins can occur when a fertilized yolk sac splits into two separate embryos, or when two or more yolk sacs are fertilized by different sperms at the same time," JTP explains.

"In our case here, these twins seem to be two separate embryos sharing one yolk sac."

Responding to queries by IFL Science, JTP explains that there are generally two distinctions in terms of sea turtle twinning. The first of which involves conjoined twins, in which two turtles share the same body, but with multiple appendages. The other distinction, like the twins found by JTP, involve completely separate twins of equal size sharing the same yolk sac.

In the past, JTP has come across a wide variety of turtle specimens, each with their own unique traits that set them apart from other hatchlings, including conjoined twins with two heads, but with a single pair of front and hind flippers.

The organization also plays a huge role in protecting and nurturing the growth of several turtle species that make their way to Juara on Tioman Island. In fact, the hatchlings that are laid there have a much higher chance of survival, thanks to efforts by JTP to separate eggs from both natural and man-made threats via a dedicated hatchery.