During our school years, we all had a favorite subject. For me, science was always my favorite subject growing up and I couldn't possibly understand how anyone could ever dislike it. From elementary school to high school, science class was my favorite part of the day and I knew that it would always be a passion of mine. Flash forward and here I am, in college, majoring in Cell and Molecular Biology, building my career around what I know best: science. I recently took a biology course where I learned some of the most interesting information about what keeps our world going: reproduction.
I realize that if I tried to discuss everything interesting that I learned in the course, I would be here a while. So to keep this a little shorter, I decided to choose one of my favorite concepts from the course.
Anyone who has taken a general biology class probably remembers the terms "sexual reproduction" and "asexual reproduction". We were taught that humans reproduce through sexual reproduction, and asexual reproduction is how plants and tiny organisms reproduce. At least, that's what they told us in middle school. But what if I told you that higher, more complex organisms can reproduce through asexual reproduction? Maybe that doesn't grab your attention so I'll rephrase: What if I told you that a female turkey can reproduce without a male?
Parthenogenesis is a form of asexual reproduction where reproduction occurs from an unfertilized ovum. This basically means, that a female organism can reproduce without the help of a male. This process is seen in lower plants, some invertebrates, and few vertebrates. Some vertebrates for example, are reptiles, such as lizards, and even some birds, like the turkey I previously mentioned.
To discuss this process a little more in depth, let's look at the stick insect (Phasmatidae). The stick insect is a common participant in parthenogenesis. Note that not all species of stick insects can reproduce asexually, but the ones that can are able to reproduce sexually as well, meaning that they can switch back and forth when they need to. When stick insects reproduce asexually, they can only produce female offspring. So wouldn't this mean that there wouldn't be a need for males? Well, there is actually an entire species of stick insect that only consists of females! So yes, in this case there isn't a need for males, but there is a reason that not every species of stick insect has gotten rid of males entirely. When the female reproduces without a male, the offspring produced are clones of the mother. Because they are clones, the genetic diversity of their species is decreased. Sexual reproduction increases genetic diversity, which is an important factor to most species, hence why parthenogenesis is not very common in species, even the ones that are capable of the process. Referring back to the stick insects, when the opportunity is available, most females will choose to reproduce sexually instead of asexually. The times when they do reproduce asexually usually occur when the females don't have access to a high abundance of fertile males.
This is just a little piece of the knowledge I gained from taking that biology course, and one of the many reasons that science has stuck with me all these years. It's really a privilege to gain a deeper understanding of the intricate processes that keep our world alive. This semester, I received the opportunity to assistant teach this same course and I can't express how great it feels to know that I have a chance to spread my passion for this subject to others.
