Welcome back to Nature League! It's the second week of the month, and that means it's time for a field trip. This month has been all about sex and reproduction, and all of the ways that life on Earth makes more life on Earth. So, for our field trip, we are going to check out the National Bison Range and see all the different stories about reproduction that has led to the populations persisting here over time.

[Intro]

Reproduction is all about life making more life. The National Bison Range is home to a host of species with stories to share on this topic.

Between January and April, male mule deer will shed their antlers. We came across a group of males in the middle of growing these antlers back, and caught a glimpse of the velvet covering on these new antlers. Come mating season in late fall, the size of these antlers will be a big factor in mating success.

A few miles into our trip, we ran into a small bear, most likely a year or so in age. At first, its light coloring made it look like a juvenile grizzly bear; however, it turns out that black bears in the western United States come in all kinds of different colors due to genetic exchange. The lighter color we saw on this little one is an adaptation to living in these more open meadows, and the genes for lighter color have persisted over time because of reproduction.

A group lead by Dr. John Byers has been studying the pronghorn antelope here at the National Bison Range for the last three decades. This group researches things like female mate choice and how that affects the population.

And now, a word! Not from our sponsors, but from the dictionary.

Welcome to this month's wild word. Once a month on Nature League, we'll look at the etymology, or origin and history, of words related to nature. This month's theme is sex, so we're going to examine a word that is central to the biological goal of sexually reproduction. That word is "gamete."

Unlike some of our other wild words on Nature League, the word "gamete" isn't typically used in everyday speech. Gametes are mature sex cells like eggs and sperm, but the history of the word isn't what you might guess. The word "gamete" can actually be traced back to ancient Greek. It literally translates as "wife," and an alternated form, "gametes" means "husband." Both of these are ultimately from the ancient Greek word "gamos," and that is translated as "marriage."

And, the combination of the concept of marriage and the cells of reproduction is really neat when you think about it. Not only is there the connotation of sex and partnership, but there's the literal meaning as well. When two gametes, an egg and a sperm cell, come together, they form one whole organism; the same way that many cultures consider marriage between two partners as two separate individuals becoming on spiritual whole.

What's additionally fascinating is the history of this word's English language usage in the last few hundred years. Here's the thing, we didn't even know about gametes until technology allowed the visualization of tiny things. The first sperm cell wasn't visualized until the late 1600's, but it took another 200 years or so for scientist to understand that in humans, two separate parents contributed one cell that developed into an embryo. Interestingly enough, it was at this same time that the word "gamete" appeared in English.

So, while a formal definition of gamete is a mature male or female germ cell usually possessing a haploid chromosome set and capable of initiating formation of a new diploid individual by fusion with a gamete of the opposite sex, gamete comes from a word that literally means marriage. And, that is pretty wild.

So, before the 1800's and leading up, there were millions of bison in North America. And, in the 1800's, there wound up being a lot of hunting and exploitation, and populations of millions almost went down to zero. Because of that, both Teddy Roosevelt and other groups and organizations who cared about the bison said that they wanted to do something. So, in about 1908, about 110 years ago, they set aside this piece of land that we're on right now, and the entire purpose was for bison to be able to have somewhere to live and to grow and to persist into the future.

So, at that point, there were so few of them that they wanted to make sure that they were able to have a healthy genetic population and gene pool. That meant bringing in individuals from all over the place to make sure that when they reproduced, there was genetic diversity. So, some actually came from Texas, some from here in Montana, and some from New Hampshire. After that, and in the 1900's, about between 10 to 20 other individuals were added; but, otherwise, every bison here in this current population is a result of the reproduction of those original founders throughout the last century.

Sex is the mechanism that allows life on Earth to make more life on Earth. Long term studies of populations, like the ones in the National Bison Range, are a treasure trove of data for scientists trying to understand how life persists generation after generation.

Thanks for coming with us on this Nature League field trip. Make sure to join us next week for a De-Natured segment, where we'll explore a groundbreaking study about sex cells in humans.

[Outro]