...your right..

Birdo does it from behind... and Yoshi is taking it in.. so Birdo is a guy cuz a why would a girl be behind? and Yoshi is gay..

Proof? Mario Party 7....

Sex and Gender

According to the North American instruction manual of Super Mario Bros. 2:

"Birdo thinks he is a girl and likes to be called Birdetta. He likes to wear a bow on his head and shoot eggs from his mouth."

This statement applies to all translations of the title, including the Japanese version. In Japan, Catherine is male as well, and likes to believe that he is female. Like Birdo, he likes to be called Cathy as opposed to his real name, Catherine. In Super Smash Bros. Brawl, Birdo's trophy description describes the character as "gender indeterminate," and uses the pronoun "it" rather than gender-specific pronouns such as "he" or "she".

The confusion surrounding Birdo's gender has also been addressed in a light-hearted matter, such as when Popple pauses before settling on calling Birdo a "dame" in Mario & Luigi: Superstar Saga. More recently, in the game Captain Rainbow, Birdo is heard with a deep, male voice which gets high-pitched when she gets angry or excited. Additionally, in the game's second trailer, Little Mac from Mike Tyson's Punch-Out!! speaks about Birdo, calling her a "young lady," only to take a short break and ponder. His final verdict is "Depending on one's view point, she is a young lady." This ultimately means some or all of these Birdo characters identify with the female gender.

Powers and Abilities

In addition to eggs, Birdo can shoot fireballs from her snout, though this ability is only displayed in Super Mario Bros. 2 and its subsequent remakes. Birdo has also shown the ability to utilize her snout in a manner similar to a vacuum, using her to suck things closer to herself or even swallow them; Birdo displays this ability in both Mario & Luigi: Superstar Saga, which notably has her leeching away the health of those she sucks up, and Mario Superstar Baseball. Birdo has also shown, on occasion, to envelop people, including herself, in large eggs, in order to increase defense. She is usually classified as all-around in sports games, where she has a great deal of strength.

In Mario Golf: Toadstool Tour hitting a nice shot while playing as she will cause a rainbow to form similar to Yoshi, but rainbow abilities have since then not been seen. Birdo also has some hints of heart based power similar to Princess Peach as shown in Mario Golf: Toadstool Tour in her victory cut-scene and Mario Hoops 3-on-3 in her special shot. However, they are not as strong or as useful as Peach's hearts; which often results in comedic instances, such as when they only succeeding in charming Birdo's Golf trophy into the air for a short time until it fell down again, to her owner's great surprise.

Relationship with Yoshi

Yoshi and Birdo are often partners in sports and party games.In Mario Kart: Double Dash!!, Mario Tennis, Mario Party 7, and Mario Party 8 they are defult partners. They were seen nuzzling each other on the title screen of Mario Tennis,in wich they also share a Tennis Court. The ring Birdo wears is suggestive, but likely unconnected. On the official site for Mario Kart: Double Dash!! the description for Catherine states "Catherine appears to be Yoshi's girlfriend... or does that mean boyfriend?!". Also in Mario Hoops 3 on 3 they appear at Mario Stadium. In Mario Superstar Baseball and Mario Super Sluggers Birdo is Yoshi's Sub-captain, also they share good Chemistry.

Physical Description

Birdo's appearance

Birdo is a pink dinosaur; however, she is not the same species as Yoshi. Her head is shaped similarly to that of Yoshi's, but her mouth is quite different, as it is shaped somewhat like a funnel. Birdo's belly is white amd fairly rounded. Her body is shaped nearly identically to Yoshi's and they are approximtely the same height.

Birdo commonly wears purple eye makeup. In her team name, "Birdo Bows", from Mario Super Sluggers, she wears lipstick, which is odd because she doesn't use lipstick during the game, nor in most of her other appearances. She hasn't hair and atop her head is a massive red bow, and on her left hand is a large diamond ring, the origins of which are unknown. In the Mario Football series, Birdo wears a two-piece soccer outfit composed of a jersey and shorts. In the Japanese commercial for Super Mario All-Stars, she wears a very expensive black dress, adorned with a black necklace with many pearls, also she wears a white stole, and a very elegant fan.

Source: http://www.mariowiki.com/Birdo#Sex_and_Gender

Birdo: Gender Pretender
Specials

Under the red bow, diamond ring, and pink scales is one very confused dinosaur.

In Japan, Birdo (known as "Catherine") is a guy who thinks he's a girl. American gamers got a glimpse of Birdo's true self in the Super Mario Bros. 2 manual, which said, "He thinks he is a girl and he spits eggs from his mouth. He'd rather be called 'birdetta.'" After Birdo's small role in Wario's Woods, Nintendo of America put the kibosh on the idea of a transvestite dinosaur when Mario Tennis (N64) simply referred to Birdo as a female.

Birdo remained a female in the U.S. from Mario Tennis (2000) up to Super Smash Bros. Brawl (2008). Directed by Kirby creator Masahiro Sakurai, Brawl included a Birdo trophy, just like Super Smash Bros. Melee. Unlike Melee, however, Brawl's Birdo trophy description was unsure of the gender: "A pink creature of indeterminate gender that some say would rather be called Birdetta." The description went on to refer to Birdo with the vague pronoun "it."
Bird calls

Birdo's voice has changed about as much as her gender. Although she is supposed to be a male in Japan, Birdo had a feminine voice in all versions of Mario's Tennis (N64) and Super Mario Advance. Starting with Mario Golf: Toadstool Tour on the GameCube (2003), Birdo only uttered low-pitched, nasal squawks. More recently, Captain Rainbow featured Birdo with a masculine voice.
Bird watching

Here's a list of Birdo's bigger roles, including any gender references.

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Yume Kojo: Doki Doki Panic - FDS, 1987

* Birdo first appeared in Doki Doki Panic, where she was named 「キャサリン」 (Catherine).
* Manual profile: 「自分をメスと思いこんで口からタマゴなどをはくヤツ。キャシーと呼ぶときげんがいい。」 (Translation: "He thinks he is a girl and he spits eggs from his mouth. He'd rather be called 'Cathy.'")
* Birdo became part of the Mario universe when Doki Doki Panic was converted to Super Mario Bros. 2 for a U.S. release.

Super Mario Bros. 2 (U.S. version) - NES, 1988

* Manual profile: "He thinks he is a girl and he spits eggs from his mouth. He'd rather be called 'birdetta.'"
* Note: The names "Birdo" and "Ostro" were switched in the SMB2 manual and game ending. These errors were fixed in Super Mario Advance.

Super Mario USA - NES, 1992

* From the "Catherine" enemy entry in the manual: 「自分を女の子だと思こんでいて、キャシーと呼ぶときげんがよくなる。」 (Rough translation: "He thinks he is a girl and would rather be called 'Cathy.'") The Japanese word used here for "thinks" is omoikomu, which roughly means "wrongly believes."

Wario's Woods - NES/SNES, 1994

* In the U.S. manual, Birdo is known as "Catherine," her Japanese name. Most likely due to lazy localization.

Super Mario RPG: Legend of the Seven Stars - SNES, 1996

* No gender specified.

Mario Tennis - N64, 2000

* U.S. manual: "Her speed lets her move around the court with ease."
* Birdo has a feminine voice in all versions of Mario Tennis.

Super Mario Advance - GBA, 2001

* In this remake of SMB2(US), Birdo has a feminine voice in all versions.
* SMA also introduces Robirdo, a giant robot version of Birdo that replaces Mouser in World 3-3.

Super Smash Bros. Melee - GCN, 2001

* Part of the U.S. trophy description: "First seen in Super Mario Bros. 2, Birdo is known for shooting eggs and fireballs from her mouth."
* Part of the Japanese trophy description: 「自分を女の子だと『思いこんど』おり、゛キャシー゛と呼ばれるとごきげんになる。」 (Rough translation: "Catherine 'erroneously' thinks he's a girl and likes to be called 'Cathy.'").

Mario Golf: Toadstool Tour - GCN, 2003

* In the U.S. manual, all the female characters have a pink dot behind them, including Birdo.

Mario Kart: Double Dash!! - GCN, 2003

* U.S. manual: "Birdo's decked out in her favorite bow and ready to race!"

Mario & Luigi: Superstar Saga - GBA, 2003

* Popple pauses before calling Birdo a dame: "This, uh...dame passed my audition perfectly, see? She's my all-new, bigger and better rookie, Birdo!"

Mario Superstar Baseball - GCN, 2005

* U.S. game profile: "A dinosaur that spits eggs from her huge mouth. Birdo is very particular when it comes to fashion, though her reliance on the color pink is a bit limiting. Her bow and ring are her pride and joy. Birdo's mouth has massive suction that can even catch a ball by sucking it in."

Mario Party 7 - GCN, 2005

* No gender specified.

Super Mario Strikers - GCN, 2005

* Though the U.S. manual avoids assigning a gender to Birdo, the Spanish manual adds a small twist to her description: "Cuando tiene el balón y está atacando, Birdo siempre supone una seria amenaza. Si buscas un compañero capaz de meter goles, Birdo es tu hombre... bueno, o mujer." (Translation: "When in possession of the ball and on the attack, Birdo always poses a serious threat. If you're looking for a sidekick who can score goals, Birdo is your man... well, or woman.") The Spanish website uses the same description.
* Game: No gender specified.

Mario Hoops 3-on-3 - NDS, 2006

* No gender specified.

Mario Strikers Charged - Wii, 2007

* The official European web site says, "Birdo's shooting is also feared by most goalkeepers, as he can score at will. His Extreme Egg can beat any goalie, resulting in quick goals."
* Game and manual: No gender specified.

Itadaki Street DS - NDS, 2007

* [?]No information available.

Mario Party 8 - Wii, 2007

* Manual: No gender specified.
* [?]Game: No information available.

Super Smash Bros. Brawl - Wii, 2008

* U.S. Birdo trophy description: "A pink creature of indeterminate gender that some say would rather be called Birdetta. A big ribbon on its head is its most distinguishing feature. In Super Mario Bros. 2, you can return fire on Birdo by jumping on the eggs shot from its mouth. Be careful not to get psyched out by fake-egg fireballs!"
* [?]Japanese trophy description: No information available.

Mario Kart Wii - Wii, 2008

* No gender specified.

Mario Super Sluggers - Wii, 2008

* Manual: No gender specified.
* [?]Game: No information available.

Captain Rainbow - Wii, 2008

* As heard in the first trailer, Birdo has a masculine voice. One of the subtitles says Atashi wa Kyasarin ("I am Catherine") -- the pronoun atashi is primarily used by females.
* Early on in the game, you find "proof" that Birdo is female, but the item is censored with a large question mark.

Source: http://themushroomkingdom.net/birdo.shtml

When asked to comment on Birdos gender, Nintendo of America responded with the following image..

Birdo ,the most mysterious character in the world. lol

Birdo is a man that identifies as a woman, and she pulls it off so well that Nintendo of America fell for it.

End of story.

Yoshi is the more confusing case, since he is a male that lays eggs. But I guess that's just how the Yoshi species works. It's rare, but possible, and other species work in similar ways in real life.

So they're both biological males, one identifies as a male and the other identifies as a female, and they're happy together. Does that make Yoshi gay? It depends on whether you think sexuality is based on the sex he's attracted to or the gender he's attracted to. Either way it's a cross-species relationship, and that's the only part that grosses me out.

Birdo?

Birdo would make a good pokemon.....just throwing that out there

 It wouldn't have the best moveset..

Egg Bomb.
Attract?
Fire Blast
Captivate?
Bounce?

Lyrics:

ahhhhhhh!!!!.........eeeeeegggss!!!!!!!
Bird..... OOOOOOOOOOOOOO!!!

The geek, with no beak:
He's so weak he cannot speak!
The geek, with no beak:
He's so weak he cannot speak!

Vestigial wings
And dwarven legs.
A semper fi cranium
That's got automatic eggs.
His gaping maw
Is geared to spew.
He just might be a she
So Birdette will do!!

Go eat your eggs!
Force fed, force fed.
Go eat your eggs!
Out of his mouth-
Straight at your head!!

With purple pants,
(They start to tear)
I reach out with all my might to
Poke out an eye.
I poke out an eye!
I poke out an eye!

My seven year old smile:
Vanishing!
Eggs,
Why eggs?!
It's breaking my heart.
It's hurting my nose.
It's turning my skin green!
Why did you have to be so mean?!

In my dreams I despise you
More than you'll ever know.
Even when I speak your name
It makes me fucking choke!

Bird...... YAYAYAYAYAYAYA!!!

Bird......

Throw it back!
Throw it back!
Throw it back!
Throw it back!

Throw it back!
Throw it back!
Throw it back!
Throw it back!

--------------So Horse the band is leaning toward the birdette thing were He might be a she------------