Difference Between Semelparity and Iteroparity

The key difference between semelparity and iteroparity is that semelparity is the feature of having a single reproductive episode before death, while iteroparity is the feature of having multiple reproductive cycles over the course of its lifetime.

Reproduction is one of the essential biological processes occurring in living organisms. In fact, it is a fundamental feature of living organisms. Each organism is a result of reproduction. It may be a result of asexual reproduction or sexual reproduction. Some organisms die soon after reproducing once. However, others reproduce repeatedly during their lifetime. Semelparity is the death after first reproduction, while iteroparity is the ability to reproduce multiple times over the course of its lifetime.

CONTENTS

1. Overview and Key Difference
2. What is Semelparity 
3. What is Iteroparity
4. Similarities Between Semelparity and Iteroparity
5. Side by Side Comparison – Semelparity vs Iteroparity in Tabular Form
6. Summary

What is Semelparity?

Semelparity describes the death of a species after the first reproduction process. In other words, semelparous species die soon after they reproduce for the first time. Many plant and animal species are semelparous. Especially, short-lived annual and biennial plants such as all grain crops, and many herbaceous vegetables are semelparous plants. Furthermore, certain invertebrate species, including many spiders and salmon, are semelparous animals. Furthermore, in Australia, there are few semelparous mammals.

Since semelparous organisms reproduce only once, their reproduction is fatal, and result in many small offspring.

What is Iteroparity?

Iteroparity is the feature of having multiple reproductive cycles over the course of its lifetime. Thus, iteroparous species reproduce repeatedly. Botanists use the word Polycarp to explain iteroparity in plants. Most perennial plants are iteroparous. Moreover, most long-lived animals are iteroparous. They produce large and few offspring.

Humans are iteroparous organisms. We are capable of having offspring several times during our lifetime. Similarly, many mammals are iteroparous. Moreover, birds, most fish species and reptiles are iteroparous.

What are the Similarities Between Semelparity and Iteroparity?

• Semelparity and iteroparity are two classes of possible reproductive strategies available to living organisms.
• Both types of organisms produce offspring to maintain their populations.

What is the Difference Between Semelparity and Iteroparity?

Semelparity is defined by a single, highly fecund bout of reproduction, while iteroparity is defined by repeated bouts of reproduction throughout life. So, this is the key difference between semelparity and iteroparity. Semelparous organisms die after the first reproduction. In contrast, iteroparous organisms live to reproduce repeatedly.

Moreover, semelparous organisms are usually short-lived, while iteroparous organisms are usually long-lived. When considering the offspring production, semelparous organisms produce many small offspring, while iteroparous organisms produce large few offspring. Therefore, this is an important difference between semelparity and iteroparity.

The below infographic summarizes the difference between semelparity and iteroparity.

Summary – Semelparity vs Iteroparity

Semelparity and iteroparity are two types of reproductive strategies seen in living organisms. Semelparity refers to the species which die after the first reproduction. In contrast, iteroparity refers to the species having multiple reproductive cycles during their lifetime. Thus, this is the key difference between semelparity and iteroparity. Usually, semelparous organisms are short-lived, while iteroparous organisms are long-lived. Furthermore, semelparous organisms produce many small offspring, while iteroparous organisms produce a few large offspring.

Reference:

1. “Semelparity and Iteroparity.” Knowledge Project, Nature Publishing Group, Available here.
2. “Semelparity and Iteroparity.” Wikipedia, Wikimedia Foundation, 3 Dec. 2019, Available here.

Image Courtesy:

1. “Oncorhynchus nerka 2” By David Menke –  originates from the National Digital Library of the United States Fish and Wildlife Service (Public Domain) via Commons Wikimedia
2. “Sow with piglet” By Scott Bauer, USDA – (Public Domain) via Commons Wikimedia