Gender-based Evolution

Gender-based Evolution refers to Pokémon that evolve if they have a certain gender in the Pokémon games. This method of Evolution was introduced in Generation IV.

List of gender-based Evolutions

Previous Evolution		Gender-based Evolution			Later Evolution
Introduced in Generation IV
Ralts Psychic Fairy	Level 20+ →	Kirlia Psychic Fairy	+ Dawn Stone Male only →	Gallade Psychic Fighting	Gallade does not evolve
Snorunt is the lowest in its line		Snorunt Ice	+ Dawn Stone Female only →	Froslass Ice Ghost	Froslass does not evolve
Burmy is the lowest in its line		Burmy Bug	+ + Level 20+ Female only + Plant Cloak →	Wormadam Bug Grass	Wormadam does not evolve
			+ + Level 20+ Female only + Sandy Cloak →	Wormadam Bug Ground
			+ + Level 20+ Female only + Trash Cloak →	Wormadam Bug Steel
			+ Level 20+ Male only →	Mothim Bug Flying	Mothim does not evolve
Combee is the lowest in its line		Combee Bug Flying	+ Level 21+ Female only →	Vespiquen Bug Flying	Vespiquen does not evolve
Introduced in Generation VII
Salandit is the lowest in its line		Salandit Poison Fire	+ Level 33+ Female only →	Salazzle Poison Fire	Salazzle does not evolve

List of other evolutionary branches

These are their evolutionary branches other than gender-based Evolutions.

Previous Evolution		Evolution			Later Evolution
Introduced in Generation IV
Ralts Psychic Fairy	Level 20+ →	Kirlia Psychic Fairy	Level 30+ →	Gardevoir Psychic Fairy	Gardevoir does not evolve
Snorunt is the lowest in its line		Snorunt Ice	Level 42+ →	Glalie Ice	Glalie does not evolve

In the core series games

Several Pokémon can only evolve to a certain species depending on its gender. All the available gender-based Evolutions are either triggered at a certain starting level or by the use of the Dawn Stone.

Combee and Salandit are unable to evolve if they are male. However, if either of them holds an Eviolite (an item usable by Pokémon who have not yet fully evolved), it still has the same effect on them regardless of their gender.

In the spin-off games

Pokémon Mystery Dungeon series

There are no gender-based Evolutions in Pokémon Mystery Dungeon: Red Rescue Team, Blue Rescue Team, and Gates to Infinity.

Pokémon Mystery Dungeon: Explorers of Time, Explorers of Darkness, Explorers of Sky, and Gates to Infinity

In Pokémon Mystery Dungeon: Explorers of Time, Explorers of Darkness, Explorers of Sky, all the gender-based Evolutions introduced in Generation IV are available. Much like in the core series games, the Pokémon needs to have the correct gender in order to evolve.

Super Mystery Dungeon

In Super Mystery Dungeon, all the methods of Evolution other than Evolution by level are not required in order to evolve.

In this game, the Pokémon have no gender. All the gender-based Evolutions introduced in Generation IV are available in-game, but those Pokémon can simply evolve with no requirement.

Pokémon Mystery Dungeon: Rescue Team DX

In Pokémon Mystery Dungeon: Rescue Team DX, all the methods of Evolution other than Evolution by level were replaced by Evolution Crystals.

In this game, the Pokémon have no gender. All the gender-based Evolutions introduced in Generation IV are available in-game, but those Pokémon evolve by spending Evolution Crystals instead of having a specific gender.

In animation

Pokémon the Series: Diamond and Pearl

In Some Enchanted Sweetening!, Cheryl's three Wormadam were all revealed to have evolved from female Burmy during her attempt to find a male Burmy. After successfully capturing one, she trained him until he evolved into Mothim.

In A Grand Fight for Winning!, Zoey's Kirlia was revealed to have evolved into Gallade.

Pokémon the Series: Sun & Moon

In Turning Heads and Training Hard!, Tupp bragged about how his male Salandit was due to evolve any day now because of its battle experience, seemingly unaware that male Salandit cannot evolve.

In the manga

Pokémon Adventures

Omega Ruby & Alpha Sapphire arc

In Metagross Investigates, Sapphire's male Kirlia, nicknamed Kirly, evolved into a Gallade by the use of a Dawn Stone.

Trivia

The Dawn Stone is only known to work for gender-based Evolutions, specifically evolving male Kirlia and female Snorunt into Gallade and Froslass respectively.
- These are the only cross-generational gender-based Evolutions, specifically evolving Generation III Pokémon into Generation IV Pokémon.