Life Cycle of a Butterfly: A Fascinating Journey Explained

Butterflies are fascinating insects known for their colorful wings and graceful flight.

They undergo a remarkable transformation during their life cycle, which includes four distinct stages: egg, larva, pupa, and adult.

This process, known as complete metamorphosis, is essential for the butterfly’s development and survival.

The butterfly’s journey begins with a tiny egg, usually laid on a specific host plant that will provide nourishment for the growing caterpillar.

Once hatched, the larval stage begins, and the caterpillar spends most of its time eating and growing.

As the caterpillar grows, it sheds its skin during a series of instars, allowing for expansion until it enters the pupal stage.

Inside the protective case, called the chrysalis or pupa, the caterpillar undergoes a remarkable transformation as its body reorganizes into the adult butterfly.

This metamorphosis can take as few as five days in some species, after which the adult butterfly emerges, ready to find a mate and continue the life cycle.

Life Cycle of a Butterfly: Stages

Egg

The first stage in a butterfly’s life cycle is the egg.

Female butterflies lay their eggs on specific host plants, providing caterpillars with a food source once they hatch.

The eggs usually take around four days to hatch, but this may vary depending on the species and environmental conditions.

Monarch Butterfly Egg

Caterpillar

Once the eggs hatch, the larval stage begins, forming a caterpillar.

These caterpillars feed on the host plant, growing and molting through a series of growth stages called instars.

As they grow, their main function is to eat and store energy for the metamorphic process.

Some key characteristics of caterpillars include:

• Predominantly herbivorous diet.
• Develop through a series of growth stages or instars.
• Undergo several molts as they grow.

Monarch Caterpillar

Pupa

After the caterpillar has reached its final instar, it forms a chrysalis or pupa, entering a seemingly inactive state.

This stage is crucial for undergoing the complete metamorphosis process, where the caterpillar breaks down and reforms its body structure.

Pupa Stage Features:

• Protective outer shell, usually well-camouflaged.
• Internal reorganization and transformation.
• Immobility, as it does not eat during this stage.

Monarch Chrysalis and Aphid Wolf

Adult Butterfly

Finally, the adult butterfly emerges from the chrysalis, with wings and reproductive organs fully developed.

Adult butterflies have a primary function to mate and reproduce, ensuring the continuation of their species.

With this information, you now have an understanding of the four main stages in a butterfly’s life cycle: egg, caterpillar, pupa, and adult butterfly.

The beautifully complex process of metamorphosis allows butterflies to transition from one stage to the next, ensuring their growth, survival, and reproduction.

Adult Monarch Butterfly

Predators and Threats

Butterflies, with their vibrant colors and delicate wings, are not just objects of beauty; they are also a crucial part of the food chain.

At every stage of their life cycle, they face threats from various predators. Additionally, human activities have introduced new challenges to their survival.

Egg Stage

• Natural Predators: Many insects, such as ants, beetles, and true bugs, feed on butterfly eggs. Some birds and mammals might also consume them when they come across them.
• Example: The Green Lacewing’s larvae are known to be voracious eaters of butterfly eggs.

Green Lacewing Larva

Caterpillar (Larva) Stage

• Natural Predators: Birds are the primary predators of caterpillars. However, spiders, wasps, and other insects like assassin bugs and ladybugs also prey on them. Some wasps are parasitic and lay their eggs inside caterpillars; when the eggs hatch, the wasp larvae consume the caterpillar from the inside.
• Example: The Ichneumon Wasp is notorious for its parasitic relationship with caterpillars.

Pupa (Chrysalis) Stage

• Natural Predators: Birds, rodents, and snails can feed on the pupa. Some insects, such as parasitic wasps and flies, can also attack the pupa.
• Example: The Brachonid Wasp lays its eggs in butterfly pupae. Once the eggs hatch, the larvae feed on the pupa, eventually killing it.

Adult Butterfly

• Natural Predators: Birds are the most common predators of adult butterflies. However, spiders, praying mantises, dragonflies, and even some species of ants and beetles can catch and eat butterflies.
• Example: The Praying Mantis, with its swift predatory skills, can catch and consume adult butterflies.

Human-induced Threats

• Habitat Destruction: Urbanization, agriculture, and deforestation have led to significant habitat loss for butterflies. Many species rely on specific plants or environments, and the loss of these habitats can be devastating.
• Climate Change: As temperatures rise and weather patterns change, the habitats suitable for butterflies shift. Some species might not be able to migrate quickly enough to these new areas, leading to population declines. For instance, the Edith’s Checkerspot butterfly has been moving to higher altitudes due to changing climate conditions, but not all species have the ability to adapt in this manner.
• Pesticide Use: The use of pesticides in agriculture can have lethal effects on butterflies, especially during their vulnerable caterpillar stage. For example, the Monarch butterfly populations have been impacted by the use of herbicides that kill milkweed, their primary food source.

In conclusion, while butterflies face numerous natural threats, it’s the human-induced challenges that are rapidly amplifying their risk of decline.

Conservation efforts are crucial to ensure these beautiful creatures continue to grace our planet.

Anatomy of a Butterfly

Antennae

Butterflies have unique antennae compared to other insects.

Their antennae are club-shaped with a long shaft and a bulb at the end. These antennae help them with:

• Sensing the environment
• Navigating
• Finding food

Wings

Butterflies have two pairs of wings covered with colorful scales. These scales are the reason for their vibrant patterns. Scales have different functions:

• Camouflage
• Attracting mates
• Thermoregulation

Compound Eyes

The compound eyes of butterflies enable them to see in multiple directions simultaneously. Key characteristics include:

• Thousands of tiny lenses called ommatidia
• Wide field of vision
• Detection of movement, color, and light

Exoskeleton

A butterfly’s exoskeleton provides structural support and protection. Important attributes are:

• Made of chitin, a tough yet flexible material
• Protects internal organs
• Aids in muscle attachment

Host Plants and Feeding

Caterpillar Food Sources

Caterpillars rely on specific host plants for their survival, as these plants provide the nutrients they need during their larval stage. S

ome well-known host plants include:

• Milkweed: Monarch caterpillars feed exclusively on milkweed plants
• Fennel: Black swallowtail caterpillars often choose fennel as their host plant

Black swallowtail caterpillars

Adult Feeding Habits

Adult butterflies feed on nectar from various flowering plants.

They are particularly attracted to the colors red, orange, yellow, blue, and purple in feeders.

Furthermore, they rely on nectar-rich plants in their habitats, which include:

• Milkweed: Both nectar source and host plant for Monarch butterflies
• Flowering plants: Provide essential nutrients for adult butterflies’ survival

To sum up, the life cycle of butterflies highly depends on host plants as food sources for caterpillars and nectar-rich plants for adult feeding habits.

Behavior and Characteristics

Mating and Reproduction

Butterflies, like the monarch butterfly, mate and reproduce in their adult stage of life.

Males will court females by releasing chemicals to attract them. Examples of large butterflies include the queen alexandra’s birdwing.

Camouflage and Defense

Butterflies use various strategies to protect themselves, such as:

• Camouflage: Blending in with leaves or flowers
• Mimicry: Resembling other, more dangerous insects

Migration Patterns

Certain butterfly species, like the monarch butterfly, engage in long-distance migration to find suitable habitats and resources.

Notable Butterfly Species

Monarch Butterfly

The life cycle of the Monarch butterfly includes four stages: egg, larva, pupa, and adult.

Female Monarch butterflies can lay between 100 to 300 eggs during their lifespan, with the eggs hatching about four days after being laid.

Some features of Monarchs include:

• Distinct orange and black wings
• Migratory behavior, traveling long distances each year

Queen Alexandra’s Birdwing

Queen Alexandra’s Birdwing is one of the largest butterfly species in the world. Some characteristics of this tropical butterfly include:

• Females can have a wingspan up to 11 inches (28 cm)
• Males display iridescent blue and green wings

Unfortunately, Queen Alexandra’s Birdwing is considered an endangered species due to habitat loss and deforestation.

Queen Alexandra’s Birdwing. Source: Natural History Museum , CC BY 4.0, via Wikimedia Commons

Swallowtail Butterflies

Swallowtail butterflies are known for their prominent “tails” on their wings.

This family of butterflies includes over 600 species worldwide. Some common features among Swallowtails include:

• Colorful wings, often with patterns mimicking other species
• Caterpillars that transform dramatically during the pupal stage

Conclusion

Butterflies, with their mesmerizing colors and patterns, embark on a captivating journey from egg to adulthood.

This intricate life cycle, comprising the egg, caterpillar, pupa, and adult stages, showcases nature’s marvel of metamorphosis.

While they face natural predators at every turn, human-induced threats like habitat destruction, climate change, and pesticides pose even greater challenges.

Understanding and appreciating their life cycle and the threats they face is pivotal for their conservation and the continued enchantment they bring to our world.

Reader Emails

Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.

Letter 1 – Collecting Butterflies in Costa Rica

Subject: Butterflies Costa Rica
November 22, 2013 10:41 am
Where can I legally collect butterflies in Costa Rica as a tourist.  Visiting in December.
I know I cannot catch them in the National Parks.  Are there areas where it is ok?
Signature: Tor Bredal

Hi Tor,
We don’t know the answer to your question.  Since we do not endorse the collection of insects for anything but scientific purposes, we will not research this matter, but we would urge you to consult with customs prior to your trip. 

Though you may be able to locate someone with private property who permits collecting insects, leaving Costa Rica with potentially protected insects and returning to you native land with contraband might result in criminal detainment.

Hi Daniel
Are you telling me that all butterflies collected in Costa Rica are potentially protected
Species?
Best regards
Tor

Hi again Tor,
We are not saying that.  We do not know the laws for collecting within Costa Rica or for passing through customs, but we would not want you to be detained for trying to export insects. 

There is big money in contraband protected butterflies.  Our friend Julian Donahue, the lepidopterist, always secured government permission prior to collecting on trips.  We are urging you to research this matter thoroughly.  We will contact Julian to see if he can provide a comment to this posting.

Thank you that would be very helpful. The Costa Rican Embassy in Norway did not know anything. I know much about Red List and which ones that are threatened. To apply for a permission would be of interest.
Best regards
Tor

Julian Donahue explains butterfly importation restrictions
The U.S. Fish and Wildlife Service is responsible for overseeing the importation of animals and their products (the Department of Agriculture oversees the importation of plants and plant products).

All such items must be declared upon re-entering the U.S.; if the Customs Inspector finds undeclared items, you will be referred to the wildlife officer and subject to confiscation and/or legal action. Permits are generally required in advance if wildlife items are being imported for commercial purposes.

The Fish and Wildlife Service enforces foreign laws: if a permit is required to collect in and/or export from the country of origin (regardless of what the local residents may tell you to the contrary), then you will have to produce that documentation when entering the U.S. Otherwise, your specimens may be confiscated.

Regardless of whether the country of origin requires permits to collect and/or export, a Declaration for Importation or Exportation of Fish or Wildlife Form 3-177 must be filled out; the form is available online at: http://www.fws.gov/le/declaration-form-3-177.html

A quick Google search (which also showed this very What’s That Bug post on the first page) produced information on obtaining permits for scientific research, but nothing that specifically applies to avocational/recreational collecting.

You may want to view these pages, however, which have contact information that will allow you to pursue this question further with the various Costa Rican authorities:
http://www.theskepticalmoth.com/collecting-permits/
http://soltiscentercostarica.tamu.edu/content/guidelines-research-and-collecting-permits-costa-rica

Although I am not aware of any Costa Rican butterflies that are on any official lists of protected species, travelers should be aware that many fish and wildlife products are prohibited from entry into the U.S. I recently visited a USFWS warehouse in Denver, Colorado, that was crammed to the rafters with confiscated wildlife, from furs and feathers to bags full of purses made from toads, and shelves full of turtles, coral, seashells–and butterflies!. For further information on items that may be prohibited, see
http://www.fws.gov/le//tips-for-travelers.html

Additional information may be obtained from the USFWS Office of Law Enforcement
(http://www.fws.gov/le/ports-contact-information.html)

Julian

Letter 2 – Artist Wants information on Butterfly Garden

Subject: butterfly host plant gardens in south pasadena
Website: daitoyofuku.com
May 1, 2013 1:16 pm
Hi I’m planting a couple gardens in so. pas./highland park (south pas. community garden, residential backyard) with a focus on native caterpillar host plants, as an ongoing art-project of sorts.

I’ve done a lot of research and am constantly looking for butterflies in the area these days. I would love some advice/input on what species of butterflies you’ve come across in the general east side area. I’ve started a google map to record sightings https://maps.google.com/maps?hl=en&tab=ml

I’m an artist who recently graduated from CGU, and when I saw that Daniel is an art professor and friend of Lisa Anne Auerbach (my former housemate adopted a wonderful cat from her), I thought wow this dude is cool.
Thank you!
Best wishes,
Steve
Signature: steve wong

Dear Steve,
This is a very complicated question, and we will have to work on it in stages.  First, we believe you have overated Daniel’s cool factor. 

He has been working with the Mount Washington Beautification Committee (including retired Natural History Museum of Los Angeles lepidopterist Julian Donahue) on a Butterfly Garden in Elyria Canyon Park for two years now, and since there is no irrigation and we just had a very dry winter, many plants did not survive. 

You have the right idea to plant larval foodplants, but many times they are not as showy as nectar plants, so they are overlooked when setting up a butterfly garden.  Striking a balance between nectar plants and foodplants, and natives versus introduced plants is a challenge. 

Many common local butterflies do not feed on natives, or have adapted to feeding on cultivated plants since natives are often in short supply.  An easy place to start is with milkweed, which is both a nectar plant and a larval foodplant for the Monarch butterfly. 

Native milkweeds include Asclepias eriocarpa, Indian Milkweed, and Asclepias fascicularis, the Narrow-Leafed Milkweed.  Both plants are perennials that die back in the winter and resprout in late spring.

You might want to begin planning your garden with a few select native trees.  The Western Tiger Swallowtail was our largest local butterfly prior to the introduction of the Giant Swallowtail.  The caterpillar of the Giant Swallowtail feeds on the leaves of non-native citrus.  T

he caterpillars of the Western Tiger Swallowtail feeds on the leaves of native Western Sycamore, Platanus racemosa.  You can also plant a Western Willow, Salix lasiandra.

The leaves of the Western Willow are eaten by Western Tiger Swallowtail caterpillars as well as the caterpillars of the Mourning Cloak, another large native butterfly that is relatively common because it also feeds on the leaves of the cultivated Chinese Elm.

Other excellent native nectar producing plants are Mule Fat (Baccharis salicifolia), California Buckwheat (Eriogonum fasciculatum) and Long-Stemmed Buckwheat, (Eriogonum elongatum).  Both Buchwheats have the added advantage of providing food for the caterpillars of several species of Blues and Hairstreaks, tiny butterflies that can sometimes be especially numerous. 

We hope this helps you in your plans.  We are attaching our list of plants targeted for our own butterfly garden and since Mount Washington is adjacent to Highland Park, you should get many of the same species.

Thank you so much for the advice! Yes, I think milkweeds are a great idea, I’m growing about 50 (mostly A. fascicularis, a handful of eriocarpa) seedlings right now.
I don’t have any places that can handle the size of a sycamore (i wish i could, they are my fav. tree) but I think I’ll be able to plant willows! I was not aware of them as host plants, so I’m psyched to learn about them. I’ve got some garden space that can handle them i think.

If you’d like to have some plants to replace the ones that did not survive the winter, let me know, perhaps I can start some seedlings and get them up to speed for fall planting.

I’ll keep you updated on progress if you like, and the link to the butterfly sightings map didn’t work, but this should:

http://goo.gl/maps/nei6m
I’ve added you as a collaborator, just in case it might interest you.
Thanks again, your website is such a wonderful thing.
Best wishes,
Steve

Hi Steve,
We would love to get additional milkweed plants.  Please post a comment to this posting so that we can easily contact you and please update the posting when you have additional information.  I have a native willow I can probably part with.

Letter 3 – Big Greasy from Australia

PLease help.
Hello,
I took these pictures whilst on a beach in Queensland, Australia. Now I am back in England I am having great difficulty finding out what it is (with Latin name) for a photo competition. Can anybody help. regards,
Chris Carter

Hi Chris,
Your lovely butterfly, Cressida cressida, has been saddled with the unfortunate common name, the Big Greasy, due to its transparent wings. TrekNature also indicates: “It is a taxanomic puzzle as its closest relatives are to be found in Argentina. ” The Big Greasy was featured on a stamp in Australia in 1997.

Letter 4 – Blue from Scotland

Butterfly? Hi bugman,
Love your website, it is an education and a delight! I took the attached photo last summer next to the sea shore in the north of Scotland, do you have any idea what it is? Is it a type of “*Coral Hairstreak*” perhaps? Kindest regards,
Scott

Hi Scott,
Hairstreaks are in the family Lycaenidae, the Gossamer Winged Butterflies. This is a Blue, also in the family Lycaenidae, but in the subfamily Polyommatinae.

Letter 5 – Book Review: Butterflies photography by Thomas Marent

Stay tuned for our review

Subject: Butterflies Book
Website: http://www.fireflybooks.com/
November 25, 2015 1:42 pm
Hi Daniel,
I’ve been reading through your blog and there is so much amazing information here! I’ve seen bugs that I never knew existed before. What a great resource on the web.
I’m writing because I think your readers will love our new book, Butterflies. The book features some of the most colorful, spectacular and sometimes weird examples of the world’s butterflies and moths. Thomas Marent’s stunning photographs provide a close-up view of the remarkable family of insects known as Lepidoptera.

The macro photography complements the enlightening text written by zoologist Ronald Orenstein, who explains the scientific curiosities of these amazing insects. Examples include such seldom-seen species as the green dragontail (Indonesia), Mexican kite-swallowtail (Costa Rica), the alpine black swallowtail (China) and European sulphurs.
Would you like a review copy? If so, send me your mailing address and I’ll send one off to you.
Best,
Caroline
Signature: Caroline Young

December 2, 2015
Dear Caroline,
The Butterflies arrived today and we haven’t opened it yet.  We cannot get past the stunningly beautiful cover image of an amorous pair of Marbled White Butterflies (see Butterflies).  Do you have an image to accompany the posting we will be writing?

Letter 6 – 88 Butterfly

Hi there,
Could you please identify this racing butterfly from Colombia?
Thanks
Daniel

Hi Daniel,
Your lovely little butterfly is in the genus Callicore, and the many species in this genus are collectively known as 88 Butterflies because of the markings on the hind wings. According to Evan Summer’s website:

“This genus is found from Mexico to South America. The upper side is dark with a metallic band on the forewing while the underside is red, white, and brown with numbers such as 69, 88, 96 on the hind wing.” Your friendly specimen actually looks like it has the number 89 on its wing.

Letter 7 – 88 Butterfly from the Brazilian/Argentine Border

Beautiful butterfly/moth..
Hi,
I saw this when I was in South America, on the border of Brazil and Argentina (Iguazu Falls). What is it?? The “88” design is interesting.. is that used to scare away predators? Thanks,
Matt from Boston

Hi Matt,
The common name for butterflies in the genus Diaethria is quite descriptively, 88 Butterflies, or in some cases 89 Butterflies. If memory serves us correctly, there are members in the genus that have markings more like 80 and 90 and they have common names that apply. Butterflies in the genus Diaethria range from Mexico to Paraguay according to Wikipedia.

Letter 8 – Cassius Blues Mating

Whats my Moth/Butterfly????
I live in Port Charlotte, FL. I was taking my dog out back when I came across, and apparently disturbed these two moths, or butterflies. Can you tell me which it is…….Thanks
Megan

Hi Megan,
We believe these are mating Cassius Blues, Leptotes cassius, based on an image we located on BugGuide. They are Gossamer Winged Butterflies in the family Lycaenidae.

Letter 9 – Common Eggfly Butterfly from Australia

Something for your database – Hypolimnas bolina nerina
Hi guys,
Got this photo today of a female Common Eggfly Butterfly, Hypolimnas bolina nerina, family Nymphalidae. The males are common and numerous but this is the first female I’ve had the chance to photograph. Taken 15th March 2008, Gold Coast. Queensland. regards,
Trevor Jinks
Australia

Hi Trevor,
We always enjoy the photos you send. We are happy to get your photo of a Common Eggfly Butterfly.

Letter 10 – Marine Blue laying

Subject:  Marine Blue Laying an Egg
Geographic location of the bug:  West Los Angeles
Date: 07/23/2019
Time: 04:23 PM EDT
Your letter to the bugman:  Hi Bugman,
It may be silly, but I can’t tell you how excited I am to get a picture of a Marine Blue laying eggs.  I’ve been watching them for years in my back yard and rarely ever see them sitting still.
How you want your letter signed:  Jeff Bremer

Dear Jeff,
Your image is great, and there is nothing silly about getting excited about getting an image of a Marine Blue laying an egg.  Was the chosen plant plumbago?  According to BugGuide:  “Caterpillar hosts: Leadwort (Plumbago) and many legumes including alfalfa (Medicago sativa), milkvetch (Astragalus), and mesquite (Prosopis).”

Letter 11 – Banana Skipper Eggs from India

Subject: Unidentified pinkish insect eggs. Help!
Location: Bangalore, India.
October 7, 2014 9:20 pm
I was at a friend’s house, photographing parakeets, when I found these eggs stuck on the leaf of a banana plant. They looked really pretty, with the red dot in the middle and the lines radiating from it. None of the people we asked seemed to be able to identify what insect these eggs belonged to. Could you help us out here?
The picture was taken on October 1st, at 11 am. The weather around here is rainy right now.
Thank you! 🙂
Signature: Mollika M.

Our Automated Response:  Thank you for submitting your identification request.
Please understand that we have a very small staff that does this as a labor of love. We cannot answer all submissions (not by a long shot). But we’ll do the best we can!

Hello,
Thank you for the response. I did a bit of searching myself, and I have figured out where the eggs came from. They belong to a Banana Skipper Butterfly (http://en.wikipedia.org/wiki/Erionota_thrax). The species is very common around here, so it checks out.

Thanks for letting us know.  Eggs can be very difficult to identify, and knowing the plant upon which the eggs are found is a great help.  We did find an image of Banana Skipper eggs on Hawaii Plant Disease.