North America and Antarctica were connected more than one billion years ago, University researchers have shown.
An international group of scientists analysed rocks from both locations and found them to contain identical forms of the element lead.
The work builds on previous research that showed the rocks were the same age and shared chemical and geological properties.
Scientists from Edinburgh joined researchers from the University of Texas at Austin, Texas Christian University, and around the world, in the study.
They found that a land rift in Antarctica is a continuation of a rift system in North America, dating from when the two land masses were joined.
The results suggest that parts of Antarctica were once joined to what is now west Texas.
The discovery gives support to a theory that ancestral North America and East Antarctica were joined in an early supercontinent known as Rodinia.
This supercontinent is purported to have contained much of the world's land mass and spanned between the North and South poles.
North America is also known to share links with Africa.
The new discovery indicates the importance of Antarctica in piecing together geographical links between the three major continents around one billion years ago.
This latest discovery is an exciting insight into what our world would have looked like a billion years ago, and helps us understand about how the modern continents were shaped.