Link #89: The Earliest Horses Were Equal to Today’s Ducks in Size!

 

Chain of Facts - A Connection of Facts

Link #89: The Earliest Horses Were Equal to Today’s Ducks in Size!

prehistoric_horses_Mesohippus
Painting of Mesohippus, a horse-ancestor lived in the Eocene and Oligocene by Heinrich Harder, PD image.

In prehistoric times, it seems that the horse species had a very eventful time. In our last post, we explained how small- to medium-sized mammals like horses were hunted by huge birds known as Terror Birds.

However, while the horses’ size then was similar to what it is now, there was a time when horses were no larger than ducks. That’s right; the early ancestors of our current day steed were only about two feet tall! If you don’t believe us, here’s the proof.

Previous Link  in the  Chain of Facts
Next Link in the Chain of Facts




How Big Were the Ancestors of Horses?

duck_drawing

You know how large the modern horses are, but that’s not the size they started out with. In fact, there was a time when horses were no larger than a house cat or common duck.

Horses that existed about 56 million years ago only weighed about 4 kg. This means that the ancestors of modern day horses were approximately one-tenth the size of the modern horse.

In fact, there was a lot of fluctuation in the sizes of mammals like horses in a period of about 175,000 years. Before this period began, horses weighed around 5.6 kg. However, at the start of this period, the horse species lost about 30 percent of its size with horses shrinking to a point where they only weighed 4 kg.

After some time, the horse species grew in size again to 7 kg. Why did this happen? Scientists suggest that this was a result of environmental changes.

What Caused Drastic Fluctuations in the Size of the Horse Species?

thermometer_OpenClipartVectors

As per palaeontologists and other scientists, the size of the horse species fluctuated so wildly because of the change in the amount of carbon dioxide in Earth’s atmosphere.

Carbon dioxide in the atmosphere, as you may already know, plays a major role in the temperatures of the planet. When carbon dioxide levels were high in the planet’s atmosphere, the temperatures were high too. In order to cope with the high temperature levels, mammals like horses compensated by reducing their size.

Thus, when the atmospheric temperatures dropped and the climate cooled significantly, mammals grew in size once more. Effectively, scientific studies conducted on horse fossils suggest that there is a direct relationship between the size of mammals and the temperatures around them.

Will Global Warming Affect Current Species on the Planet?

Global_Warming_icon_Noun_Project

Global warming is a heated subject these days. Because of the alarming increase in global temperatures and melting polar ice caps, many scientists are worried how these changes will affect life on Earth.

You may have heard about countries coming together to find a way of countering the changing global temperatures. So, how are these new findings relevant to the modern situation of global warming?

Scientists that discovered the relationship between the sizes of prehistoric mammal species and surrounding temperatures suggest that it is difficult to say. The reason for this is that the temperature changes in prehistoric times were gradual. This allowed various species more time to adjust to the changing temperature.

Currently, the temperatures are rising drastically which doesn’t give the mammal species enough time to adjust. In effect, they can’t predict what will happen in the world if the planet’s temperatures continue to rise.




Can you Guess the Next Link in the Chain?

What will be the next link in our Chain of Facts? Think you might know? Scroll down to add a comment below with your best guess.

Previous Link  in the  Chain of Facts
Next Link in the Chain of Facts

You can view the full list of links in the chain here.


Sources:

http://www.sciencemag.org/content/335/6071/959
http://www.sci-news.com/paleontology/article00195.html

LEAVE A REPLY

Please enter your comment!
Please enter your name here