10 Animals That Give Birth and Then Die

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Nature is full of evolutionary selflessness. From deep-sea octopuses to certain marsupials, there are animals and insects that reproduce and then die, as their lives can be cut short because they focus their energy on one thing: reproduction. Scientists call this “semelparity,” and it happens more often than one would expect. Here are 10 animals and insects whose final act is creating offspring.

1. Aphids (Myzus spp.)

Aphids populate areas with moderate to hot climates worldwide. They are often present on cultivated plants, bushes, and woody plants. The typical life span of these small insects extends from 20 to 40 days. Feeding only on plant fluids, females can rapidly reproduce without sexual reproduction. Interestingly, females give live birth to genetically identical offspring (some offspring are even born pregnant). Aphids typically reproduce rapidly and until exhaustion for much of their 20-40 day lifespan, with some individuals dying from exhaustion after extended periods of reproduction.

2. Praying Mantis (Stagmomantis spp.)

Praying mantises inhabit gardens, grasslands, and forests across the world. The lifespan of a praying mantis is typically about a year. After attracting a mate and fertilization, the female deposits eggs inside a bubbly egg case called an ootheca. The gestation period lasts about 3 to 6 weeks, depending on the temperature in the region. After laying eggs, the costly output often causes her to die within weeks or months, though the exact timing can vary depending on environmental factors.

3. Labord’s Chameleon (Furcifer labordi)

Labord’s chameleon dwells in Madagascar’s dry forests. This chameleon survives for only four to five months after hatching. Following maturity, male chameleons typically die after mating. Females deposit only one clutch of eggs underground. These eggs then incubate for about 8 to 9 months and hatch during the wet season.

Males and females die off due to hormone drops and physical exhaustion. The synchronized dying helps resources go toward the next generation, potentially maximizing survival during short rainy seasons.

4. Brown Antechinus (Antechinus stuartii)

From eastern Australia, this marsupial has a short, active lifespan. Males can die during the reproductive period, but in ideal conditions, females can survive 2 to 3 years. This rough breeding season begins in early spring and can last 2 to 3 weeks. During this time, the cortisol hormone levels skyrocket for males. This surge causes internal bleeding, immune system failure, and organ malfunction.

Moreover, with a gestation period lasting approximately four weeks, many females die soon after nursing their first set of offspring due to the physical toll, though some may survive to breed a second year.

5. Mayfly (Ephemeroptera spp.)

Mayflies are common in freshwater locations. As larvae, they can live up to a year. However, when they reach maturity, they only live a short time (from several hours to a couple of days).

As adults, they lack functional mouthparts to consume food, making their sole purpose reproduction. In fact, female mayflies spread their eggs on the water within hours of emerging and end up dying in the process, but in turn maximize their reproductive output.

6. Humboldt squid (Dosidicus gigas)

These eight-armed creatures, known for their elongated bodies, are native to the Eastern Pacific Ocean. Humboldt squids have a lifespan of only 1 to 2 years. After the massive release of eggs into the water, the males and females of this animal experience a quick physical decline. They stop eating, become sluggish, and typically die a few days after the eggs are released.

In addition, the large number of offspring produced at once is a unique but useful evolutionary strategy that spreads massive amounts of offspring into the next generation, even if the adults do not survive.

7. Desert Velvet Spider (Stegodyphus lineatus)

The desert velvet spider lives in dry areas near the Mediterranean. These areas can include parts of Southern Europe, North Africa, and the Middle East.

The life span of these striped social spiders is about 1 to 2 years. Females lay eggs and protect them until they hatch. After hatching, the female regurgitates food to feed her spiderlings for several days. In the end, the spiderlings finish the job by then consuming her body. This behavior is referred to as “matriphagy,” which is a shift from self-preservation to offspring.

8. Pacific salmon (Oncorhynchus spp.)

Pacific salmon hatch in streams and rivers in North America and Asia. They move to the North Pacific Ocean to live and grow for about 2 to 7 years.

Reproduction of this species lasts a few rigorous weeks. After swimming hundreds of miles upstream to where they hatched, females dig nests of gravel. Next, in these nests, females lay thousands of eggs, which males then fertilize. After this process, females’ and males’ vitality sharply declines, and they die in about 7 to 14 days.

9. American Eel (Anguilla rostrata)

American eels live along the eastern coasts and rivers of North America. Although their lifespan is 10 to 20 years, their final exhaustive migration leads them to spawn once and then die.

Females put out millions of eggs into the open ocean, which are then fertilized by males. After spawning, their bodies stop working soon afterwards. Researchers believe that this death after spawning is due to physical tiredness from the journey and the hormonal changes that occur after this event.

10. Giant Pacific Octopus (Enteroctopus dofleini)

The giant Pacific octopus inhabits the cold coastal waters of the North Pacific. With a life span of 3 to 5 years, the females of this species lay tens of thousands of eggs that incubate for about 5 to 10 months. During this period (often referred to as the “brooding” period) females never leave, eat or rest. Her sole duty becomes watching her clutch of eggs, which involves aerating, cleaning and protecting them from predation.

The closer the eggs are to hatching, the more females lose vigor and begin to die from starvation and stress. Sadly, she dies around the time that they hatch, making it one of the biggest self-sacrifices in the animal kingdom.

A Brutal Balance

The natural environment has many species that put all of their resources into reproduction. Unfortunately, the cost of this is most often death. The Desert Velvet Spider gives itself as a sacrifice, and the salmon and eel have exhaustive migration periods where they have fertilization events, but eventually die. Such organisms demonstrate the many ways life has evolved to ensure the continuation of a species.

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